With the advantages of being able to search the internet for reviews, forum comments, YouTube demos, and other good information, I find myself doing MUCH more research before I purchase, and as a result, I get far fewer "dogs"....
When I look at the lifetime of tools and jigs I've bought and never used (or tried once) I am forced to conclude that I am more tool collector than woodworker - and that's embarrassing.
The spring loaded corner chisel..........better results with 2 hits of a stright chisel
Bought a used table saw that was not one of my favorite tools. Not so much so that I had to "resell" it with in a year.
Recently I purchased a pen that writes upside down and underwater. Cost me 16 bucks. I thought my wife was going for the Beretta to shoot me down. Now that was a good buy, but rough on the wood----
very few losers over the years, but no regrets. Even the few that haven't been useful have taught me something, and I have been fortunate not to spend heavy money for any of them.
How about a Makita planer that has a moveable table instead of cutter head. I can't use extension tables with it to eliminate snipe!