It costs time and efford to come up with detailed-enough specification :) I once wanted to take a project with BigCorp, my first offer was dead cheap since the

It costs time and efford to come up with detailed-enough specification :) I once wanted to take a project with BigCorp, my first offer was dead cheap since their requirements were consisting of two lines of text. So I gave them a feel of what I'd build for them within their tiny budget. 4 years later they still try to get somebody to build that thing for them, but specs are now 40 pages long and budget is still tiny. I dropped out 2 years ago (after providing n-th offer quoting 15x more than original quote), at the time I was already smelling a trap project, now I'm glad it went that way, I feel sorry I spent time preparing those offers.