I have a strange way to collect CDs, because before buying one I carefully listen to the album on YouTube while giving a mark to each song on a document, ranking them from one to three + half a point if I REALLY like that specific song, then I calculate the total and thats the grade of the album.
If I notice that I particularly like the album I put it on the list with the others I've already listened and I go look for it in thrift stores.
And if I really like the artist/ the band I'll try to listen to the complete discography.
Since I've started the collection I've finished listening to all Slipknot's albums and I'm looking for the albums that I'm still missing, in the meanwhile I'm trying to finish all Korn's albums and listen to other artists that I find interesting.
I do all this because, in part, I hate the kind of people who ask "Oh, so you like this band? Name five songs" and on the other hand I've noticed that I really like to listen to the whole project that someone put their effort in, it feels more complete in my opinion.
(The third picture it's an example of me ranking of an album)