I have countless bottles of sample FOs that I don't really like but will keep them on hand for when the urge strikes to do some blending...whether for pillars, containers, lotions, scrubs, rebatched soaps, etc , etc.
If I am experimenting or making something for personal use (candles, lotions, soaps, etc) I tend to use FOs that I have on hand,,,,if by chance I have an FO that has been sitting back on the shelf because I didn't really like it, I may blend a little of it with my chosen scent ...heck, I paid good money for these scents and I will use them up whenever possible.
The most often thing I do with unwanted scents is to make Fart Sprays for use in the bathroom, no MATTER what the scent is, it is better than the smell that comes out of the'bathroom behind my men!!!!!!!!!!!!