So what piece of gear have you made multiple purchases of trying to get it right?
Um, most of them.
We have had, and I will count only the last 25 family paddling years, and try to estimate accurately, if on the low side
5 stoves
12 tents
8 tarps, not counting the blue poly stuff
At least a dozen sleeping pads, from foam to self inflating.
A t least a dozen sleeping bags. Maybe more, we still have every one, filling a 6 foot wide closet.
And etc.
Funny thing is, we still have most of that gear, and it is still in good working order. But I am not taking the old Optimus when I have a Jetboil and fuel canisters, or an old polyfil bag when I can take a down bag one third the size.
Same with tents, although my wife still likes the old Timberline for set up familiarity. Boats and paddles, eh, lets not even go there, but we have only kept half of them.
There are a couple of multiple purchases that still need improved replacement. And likely will not see it.
Better quality, more durable, breathable waterproof rain jacket and pants. I know the materials and design features that make high quality raingear. I have been tempted, but I am just not willing to spend that much on a freaking rain suit.
The perfect multi use canoe. I have a pretty good idea of my ideal dimensions and shape, materials and weight. I have not been tempted, my wallet would need to weigh as much as the boat.