I am new to the niche perfume and I have been sampling a lot recently. Some fragrance I like, some not so much, but what surprises me is how many fragrances fall apart on my skin into some sort of unbearable soap. I am sure they were not intended to be like that. I had to wash them off. These fragrances include Serge Lutens Daim Blond, Amouage Gold and many L'Artisans. I wonder why it happens.
I think that one reason is the food you eat. If you eat a lot of greasy junk food, that's what you will smell like, and the frag will mix with that (in your sweat) and smell bad. Just something I've noticed.