This unhappy situation is changing, albeit more slowly than I'd like. With agile methods and interaction design, there's a lot more focus these days on building software for users rather than for process specialists or, worst of all, CIO's. Software packages are starting to show the benefits, as users expectations are raised by what they see on consumer devices.
But those process specialists and CIO's haven't gone away you know. They still pop up at contract time, demanding custom modifications that deface your beautifully honed software. Your own sales people are only too happy to go along: give the customer what he wants and charge him $200 an hour for the privilege - what's the problem? But you, software product guy, you must resist, and you must be prepared to fight the good fight in your own organization.
Your sales guys don't understand, so you need to convince your CEO as to why this is a bad idea. It's more than a question of usability, which is a fluffy concept to your alpha-male CEO anyway.
- Customization projects go wrong, frequently. Your reputation as a software vendor will suffer, not because of a deficiency in your product but because the customization is badly done.
- Many people involved in negotiating contracts with a vendor are naive when it comes to software. They think you can specify and cost everything up front, the poor things. Projects run like this often result in software that meets all the terms of the contract and none of the needs of the users. They'll complain, they'll be unhappy, and the people who actually asked for the customizations will blame you!
- Customized software is notoriously difficult and costly to upgrade. If you want a loyal customer who stays with you through many product releases you'd be best to limit the amount of customization.
- If your software needs to be heavily customized to suit a customer this could mean that either (a) your software is missing features it really needs to have or (b) this customer is not really in your target market. If (a) is true don't customize - build the generic features your customer wants in the next release. If (b) then walk away and put your attention on the market you're trying to build - this customer is diverting you from your goals.
In short, only sell customization if you really really have to - and be ready to explain to your customer why getting exactly what he wants could be a bad idea. Have them read the article Package Customization by Martin Fowler as a primer on the topic. You may actually find that your customer appreciates the advice - after all, you're the expert on software development in this relationship.