I've never actually hated any of my basses (none that I can remember anyway), but I've owned a couple that lasted about 5 minutes each - the first was a Zon Sonus, a superb bass but I instantly knew I wouldn't get on with the neck. I also bought it for the Billy Gould connection and it sounded nothing like him, unsurprisingly.
Another was a Rickenbacker 4004. Massive, clubby neck, and dull tone with none of the Rick treble I was after. Exchanged it immediately for a 4003 - much more up my street!
I still lust after the 4004 as apparently the neck is far better these days, and I could swap out the pickups for something a bit more 4001-flavoured.