Interlocking the resin and collagen - rich dentin provides better adhesion and does not rely on moisture. (sciencedaily.com)
I usually don't sand, either, but in this case I did because I really wanted to make sure I got good adhesion since cupboards get so heavily used. (thegoldensycamore.com)
Suit fabrics were little problem, the main requirement being a smooth lint - free surface to ensure good adhesion for the led strips. (treehugger.com)