What's your go-to trick for a curved stair?

Why do we all act like caulk is just decorative goop until it magically fixes our houses? I went from skeptic to believer so fast it's embarrassing (my windows were basically just fancy screens). Total game-changer for about ten bucks.

Were they just too thin to survive in there?

Last year I found a nest behind my water heater. @green.river has good advice on using steel wool, but I learned the hard way that it rusts in damp spots. After a few months, the steel wool turned orange and fell apart, letting mice back in. Now I use copper wool instead because it doesn't rust and they still can't chew through it. It costs a bit more, but it lasts way longer, especially in humid areas like basements. Just something to consider if you're sealing gaps long-term.

Your buddy's no-holes bin seems to go against the usual advice. Does he have a special method for dealing with the liquid that must build up at the bottom? A totally sealed container with wet food scraps sounds like a recipe for a smelly, soggy mess.