I continue to find essays and assertions by others that the key to achieving high-quality work, especially in the realm of software development, does not spring from cash. Software development is a highly abstract activity, and thereby demands a great deal of thinking and managing a complex web of issues and parameters. When developers go about building software, there really isn't much room for them to ponder and contemplate, "ooohh, I will $500 more and a FREE buffer lunch if we finish this on time and without defect! Yes! You can bet my two socks I'll get it done!"
Monetary rewards is probably the last thing developers think about. In any real-world project of substantial size and complexity, what's likely on their minds are when they can finally take a break for a meal, or goto bed.
The phrase that pops out quite often regarding this is called Intrinsic Motivation. It is an interesting psychological peek into what drives people to do things and achieve. Of course, that is not to state money has absolutely no place in this respect. It has a role (we need to eat and have a roof over our heads after all), but it is never the major slice of the pie. And keeping that fine balance between compensation and motivation is extremely tough indeed.