They give me money. In exchange, I do what I'm told.
Very simple, until they tell you to build a system that does X, and you do, but they didn't tell you about features X
1, X
2, and X
3, and you point this out and they say "but any idiot would have known those features are necessary", and you say "but it isn't in the spec I wrote and you approved", and they say "yes it is, it's right here in the bit that says '...all necessary functions...'". So you beg some more time to get it right, and this time you give them a daily build to ensure implementation details are clear, and all goes well until your contract is terminated for reasons only known to those resident in the
adminisphere.