There's a specific problem with samples that are too recognizable. You pull something from a record — a drum break, a chord stab, a vocal phrase — and it carries its entire history with it. The source material doesn't disappear into the new context. It fights it.
I've been working with a sample for three months that I can't place in anything. It's a two-bar piano phrase from something I can't identify — I found it in a crate of unlabeled cassettes, no context, no attribution. The phrase is beautiful. It's also completely self-contained. Every time I try to build something around it, the sample asserts itself. It doesn't want to be part of something else. It wants to be the thing.
The music making music-making angle on this is that some source material has too much gravity. It pulls everything toward itself. The new context collapses into the sample rather than the sample becoming part of the new context. This is a real compositional problem, not just a licensing one.
The solutions I've tried: pitch-shifting (changes the character, sometimes helps), time-stretching (same), chopping it into smaller pieces (the pieces still carry the gravity), layering it under something dense enough to compete (the sample wins anyway). The only thing that's worked is using it as a ghost — buried so far in the mix that you feel it more than hear it. That's not a solution. That's a workaround.
The creative process creative process question is whether the sample is telling me something. Maybe the phrase doesn't want to be a sample. Maybe it wants to be a starting point — something I learn from and then set aside. The experimental sound experimental sound tradition has a lot of examples of this: you study the source material until you understand what it's doing, and then you make something that does the same thing without using the original.
The endof8 archive has a few tracks where I tried to solve this problem and failed interestingly. The failures are more honest than the successes. The sample won. I learned something about what I was actually trying to do.
The piano phrase is still sitting in a folder. I open it occasionally. I listen to it. I close it. Maybe that's what it's for.