Sorry for obvious reaction. Already burned by this. :-)

Yes, it's a widespread problem. Crafting code for maximum maintainability is often really important and often overlooked

Maintainable code can be changed more easily than unmaintainable code. Each change will tend to make code either more or less maintainable. Over time, the probability of maintainable code being refactored into unmaintainable code approaches 1. Most older code based observed were in fact found to be unmaintainable, supporting the theory.