I just wanted to clean off a front brake pad, and due to recent neglect and a comedy of errors it sort of cascaded to the rear derailleur. I'll spare the details but after finally getting everything in shape and back together I noticed that the pulleys were needle-sharp. Thinking why put $9 pulleys in a well-used $18 DR, just buy a new one. Then upgrade fever struck. I was looking at lists on the weight weenie site, checking off gear wrap capacity and thinking about the relationship of bearings vs bushings to watts wasted, not to mention how nice anodized surfaces and an actual model name would look back there ... but in the nick of time reason prevailed and my natural cycling parsimony asserted its ascendancy.
I didn't realize how dangerous neglecting routine maintenance might be in provoking the fever. Is it a lost cause? Are you still holding out against unnecessary upgrades, or is it inevitable? Maybe constant maintenance and replacing cheap parts before temptation builds is the only cure?