The caulk job that fails in six months almost always skips this one step

Homeowners redo the same caulk job every year, blaming the caulk, when the actual failure point is almost always surface prep: caulking over old caulk residue or a damp surface, both of which prevent proper adhesion no matter how good the product is.

The fix takes ten extra minutes and gets skipped constantly: fully remove old caulk with a scraper, clean the surface with rubbing alcohol, and let it dry completely before the new bead goes down. Caulk applied to a clean, dry surface lasts years longer than caulk applied over old residue, regardless of which brand you bought.

I've redone the same bathroom seams for clients three years running before finally explaining this. The caulk was never the problem.

Part of the deeper dive: The Homeowner's Guide to Fixes That Actually Hold (Not Just Look Fixed).