Walter,

>Prove me I'm incorrect. Fact is that with tailor made software you've got a fixed set of specifications. With commercial software you don't, You've to do a lot of research and become an expert in the domain before you can make a decent program.

I'd say that for custom software you also have to do a lot of research and become an expert in the domain to properly handle the analysis and design of a good application, particularly if you are charged with writing up the specifications in the first place, which is often the case. Those who do not handle that part of the project correctly end up in those statistics we hear often about 80%+ of all IT projects ending in failure.