Tell Us about an Album That Took a Long Time to Grow on You

Captain Beefheart Trout Mask Replica
Frank Zappa Uncle Meat
Bought them both in the early 80's & got rid of them shortly thereafter. Bought them both 20 years later and have them now in rotation. 
Another one is The Grateful Dead's Reckoning album. It sounded way to country for me on first listen. Even tried to give that one away. Now it's one of my favorites, & has been for over 30 years.  

Every Peter Gabriel album !

Since Peter was mentioned i would submit US . When it came out i would only play two tracks , Digging in the dirt and Steam . This was as a teenager . The album was so uncompressed that it did not show well in my car stereo or boombox . Once a proper hifi system was has it became a jewel sonically . Not a bad track on it . A desert island selection now .

I've had many records that I was initially very disappointed in for sure. Too many to remember for sure but here are a few I lovingly do remember the struggle.

Talking Heads - Little Creatures. This album was played a lot in the electronics shop I worked in while in the Navy. At some point it clicked and I've been subliminally thinking about playing it on Spotify for a few days now. First heard it over thirty years ago.

U2 - October. It was a very difficult hump to get over but boy (no partial pun intended) what a record when I could finally "hear" it. 

Wilco, several of their records but mostly Sky Blue Sky. When I began to get it I could not turn it off for weeks (and probably months). I still think this is their best effort.

Daniel Amos - Dig Here Said the Angel. I've been a fan of this band for over three decades. I played this disc three or four or five times when I bought it and really didn't like it. Then I put it away for some time before putting it in the disc player in my car. Over repeated playing I was able to crack the code. Now, after probably several months am having trouble considering it is time to put in a new disc. I don't drive to work everyday so take that into consideration but I feel so blessed to feel this way about a record. If you've never heard this band, check them out. You may just be happy you did.

Thanks Rebbi for having the thought tostart this thread. I can't wait to read others experiences.

Three that jump to mind:

"The Good Earth" by The Feelies. It was a very different application of a similar musical idea to the one that underpinned "Crazy Rhythms", the prior (debut) record from that band. At first, I just didn’t hear that or "get" it. I guess that it just took my brain a little time to understand what they were doing.

The first White Stripes record initially struck me as a weak attempt to channel Led Zep. After a couple of years, I started to hear it as a very cool job of channeling Zep.

The first Lou Reed solo album was a disappointment after hearing what he’d done with Velvet Underground. I later came to really love the record.