Hang on to for life, that could be a long haul.I tend to keep the speakers that I can't recoupe my money from unless I sell them cheap. Makes them easier to keep and use in another area and with great benefit.
Room is my only issue I have found revisting a speaker I thought was not great actually sounded better with other front ends that came into my ownership.So they became "new"
over and over.
Your point was more about a set of loudspeakers in the same system long term ,I can see that,so far Every speaker I have had and have sound different.This quandry makes me like most of them for one reason or another.What I will add is that many people are into the hobby for hobbies sake but not so much for music.Let me say guilty as charged(hand up waving).To really get to know audio and music We have must ease up on the hobby aspect and tilt toward more listening sessions.
See if you subtract the time you use to afford,research,
shop,compare,break-in,system tweak,then our time here is short,really.People tend to get the most bang from thier 1st autos,more memories adventures,excitement with later aquisitions becoming more expensive and more statement then
practical,emotion and wallet playing a larger role.
Every speaker tends to have its own sound,I like many out there,can't own them all so your point is very valid.
Some take longer to figure it that way I suppose.
I put one old small set under eaves of house they have lasted several years there so far saved me laying out $ for new outdoor ones.Others run in less used systems but which carry certain strengths.