We all know about Plan -> Do -> Check -> Act cycle. Link to Wikipedia - http://en.wikipedia.org/wiki/PDCA. One important thing is missing here from my point of view. There must be improvement part in the center, so that we don’t forget to always improve the whole process.
Even though everything looks perfect in books, but here is the reality that i bet everybody experienced at work at least once. 🙂
There is one thing i try to do to prevent that. Slow down and step back periodically to make a reality check and focus on improvement part for selected area, which is often forgotten just because we get into a routine. So, break the habit!