Maintenance of a digital business product (e.g. a Web site, mobile app, or software) refers to the work that includes modifications made after delivery to production to fix bugs, address compliance/security issues, or improve scalability/performance These modifications can be to the product’s software code, configuration, documentation, hardware, or surrounding network.
Maintenance is often contrasted with the development of new features and functionality to enhance or increase the capabilities of the product.
The distinction between maintenance vs. new feature development comes up in both internal and external contexts. In the external context, it pertains to a maintenance contract with an outside vendor. A vendor is likely to define maintenance in strict and narrow terms to minimize costs the vendor has to incur. In the internal context it is helpful in analyzing staffing and resourcing capacity of an organization which is needed to understand the bandwidth available to work on new initiatives.
The purpose of this article is to help answer questions such as: What do you mean by maintenance work? What should we consider maintenance vs. new feature development? Is there an industry standard definition? What’s our selection criteria? Can you give some examples? Other questions that often accompany these are: What ratio of maintenance vs. new features development work is considered best practice for our industry? How does our organization’s situation compare with that? These latter two questions require analysis specific to your organization and a set of reference organizations to answer.
The following illustrates some typical attributes of maintenance vs. new features.
|Consequences of not doing||Often maintenance work is not optional, i.e. the consequences of not doing maintenance range from the gradual decline of the product to complete breakdown of the product. Not doing maintenance often causes legal, security and other compliance issues.||Implementation of new features, functionality and services is often optional. The negative consequences of not implementing new features typically include loss of competitive advantages, loss of market share, and decrease of relevance.|
|Financial impact||The financial value of an asset decreases in the absence of maintenance. Maintenance work helps maintain the value of the product, but typically does not substantially increase it.||New features and functionality increase the financial value of an asset.|
Types of Maintenance Done on Web Sites and Mobile Apps
Learning from the The International Standards Organization and International Electrotechnical Commission’s ISO/IEC 14764 specification, we define maintenance of a digital business product such as a Web site or mobile application into the following four categories:
- Corrective maintenance: Reactive modification of the software, configuration or infrastructure powering a Web site or mobile app performed after delivery to correct discovered problems. E.g.
- Bug fixes
- Install security patches to address existing security/privacy holes.
- Adaptive maintenance: Modification of a software product performed after delivery to keep a software product usable in a changed or changing environment. E.g.:
- Modifying a Web site to work with an newly emerging Web browser like a recently released version of Google Chrome.
- Modifying a mobile app to comply with changes made by third parties, e.g. new terms of service from Facebook or Twitter, a new API released by Google+.
- Increase capacity to handle increasing traffic on a Web site.
- Perfective maintenance: Modification of a software product after delivery to improve performance or maintainability. E.g.:
- Changes to servers or network to make the Web site serve quicker.
- Refactoring the software code to make it less expensive to maintain and modify.
- Preventive maintenance: Modification of a software product after delivery to detect and correct latent faults in the software product before they become effective faults. E.g.:
- Y2K :-) fixes made on or before December 1999. Remember that? When we had to install patches and test software on the Web sites in the 90s.
The following are some examples of maintenance work contrasted with new features development.
|Fixing bugs in existing software.||Developing new Web applications or mobile apps. Adding major new features and functionality to existing apps.|
|Modifying software code on a Web application to comply with changes to Facebook’s application programming interface (API).||Adding new software code to add support in a Web application for a new social network, e.g. Google+.|
|Rewriting parts of a Web application to handle increased usage (E.g. more users, users storing more data, growing traffic.)||Developing a complete new Web application to replace an existing application to address the shortcomings the previous one has.|
|Routine work like generating, analyzing and publishing periodic reports.||Designing, developing and automating a new report that has not existed before in the organization. Adding significant and major new features to an existing report.|
In certain cases, the distinction between maintenance and new development can be blurry. For example, when rewriting (rebuilding) major parts of an application to overcome its shortcomings, at what point do we consider it a replacement (new development)? In such cases, it may be subjective based on how the output of the work is classified, branded and marketed. If it is being announced, launched and sold as a great new product to replace the old, it would be new development. This can cause issues when a customer has a maintenance contract with a vendor and doesn’t want to pay for the new version that doesn’t add substantial new functionality. That, however like all contracts, becomes matter of trust, relationships and reputation.
In the cases where an external vendor has a maintenance contract with a customer, the vendor is likely to not classify certain maintenance activities as maintenance since doing so would incur significant and unexpected costs the vendor would become responsible for. For example, a vendor may not include many adaptive types of maintenance in the contract. A vendor may want to charge the client more to handle increased usage.
Ratio of Maintenance vs. New Development
There is no “magic number” answer to this question. Ratios like 80/20, 70/30, 60/40 or 50/50 are specific to an organization in a specific phase. In today’s dynamic and hyper-competitive environment, seeking a best practice ratio for an industry may be misleading. A company or project in the startup phase typically has a lot more new development than maintenance happening than a organization with a mature product. Even within a particular company, the ratio changes as new projects start, are worked on and are completed. Decommissioning obsolete products also lowers the maintenance.
Going down to maintenance mode for specific products does make good sense in certain circumstances. For example, when you are working on a major new version of the Web site or product, you can put the current (soon to be replaced) version in maintenance mode.
Sometimes, in times of financial hardship, companies try to hunker down to maintenance mode where they shed the new development work and do only the work required to “keep the lights on” to ride out the storm. This type of horizontal cutting of all products may initially seem like a good approach but in most cases, it is not a wise practice. In most circumstances of financial hardship, it is often wiser to cut products vertically. In other words, focus on doing a fewer number of products well rather than keep doing the same number of products poorly. Stopping new development and product innovation enables existing competitors to gain a huge lead over you. It creates opportunities for new competitors to your business and leads to the decline of your brand.
My article titled Trinity Method of Technology Management makes a case for decommissioning products the way Google does seasonal cleaning by ending products that no longer suit the company’s revised strategy.
- Software maintenance: Wikipedia article: http://en.wikipedia.org/wiki/Software_maintenance
- Software Engineering: Software Life Cycle Processes: Maintenance (ISO/IEC 14764:2006) [paid content, not free] http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=39064