Don't Play Whack-a-Mole
When problems or bugs arise, there is a strong temptation to apply a quick, or "band-aid" fix.
Resist this temptation!
A quick fix will often break things that were working, or worse -- something you fixed earlier.
Take time to understand the problem, its cause, and the cause of its cause.
Do a "5-Whys" analysis.
Use source control and a good change management system that lets you reference related problems and changes.
Always beware of making changes that you don't fully understand.
And once you understand the problem, be sure to make the simplest change that will solve it.
