Sorry, it’s not me, it’s you?

I'm guessing the speakers in question were not a good match for your system and/or your room. Your dealer should have done a better job of recommending a suitable speaker for your situation, otherwise you may as well buy on-line. But if you buy from a dealer, do not be afraid to ask for his opinion. That's what he there for.

Nope Never.

OH yes.  My favorite was getting speakers that in the store I LOVED.  Got them home, loved them on some stuff, hated on others.  Tried ...  Failed. ... Took them back.  Apologized.  Took my cash.  Spent days lamenting--I literally could not live without them (It was exactly like having a lover leave me).  Gathered up my courage and cash, ran back to the store, apologizing profusely, offering to pay extra for their trouble, whatever they wanted, weeping and wailing.  They laughed.  (It was a store that specialized in car audio).  "Two things" they said.  "(1) We want you to be happy.  We really do.   And (2), you know what? we just don't get people like you in here very often, and we find it very amusing."  (Still have those speakers.  A couple of years later, on a whim, I bought a cheap tube amp to replace what I thought was the entry-level hi-end amp/pre that I had bought shortly before those speakers.  The magic returned.   And I wouldn't replace those speakers for any amount of money.  It was actually quite alarming to find myself as involved in a piece of material as I was with those.

I don't think the OP made a mistake at all, they took advantage of a return policy and got to demo a set of speakers through the break in period, and returned them after being unsatisfied with them.  Nothing ventured nothing gained.

At least you don't take years to research and ponder, while listening to whatever drove you to better your listening for those same years, like someone else on here does.  Bravo for being proactive.

Flatblackround, needlebrush- how can you bash “Ike” (I know everything) MC? There are quite a few people calling him IKE for his recent posts. Justifiable, yes