Because I think the question is worded poorly, let me give my example.
For me it’s the brand name. Not its reputation or history, but just how the name sounds. For example:
Omega - association with ancient greece, and also math and physics. 10/10 would explore space with one
Cartier - sounds french and expensive, is french and expensive; perfect for if I was rich and wanted to feel rich
Baltic - reminds me of the cold Baltic sea, perfect name for a dive watch; probably one of the reasons I love the Aquascaphe so much
Names that end with “ex” - generaly sounds like you’re lazily trying to look cool (Rolex is an exception, I don’t feel strongly about it)
So yeah I know it’s dumb but the brand name is the thing that is always plastered in big letters across the dial, I feel that the name should fit the style of the watch and also myself.
Brand name is not a feature. Your answer is invalid.
For me it would be the lugs. Lug-to-lug size is crucial because my wrist is thin, but lug shape also matters a lot. The fat and convex lugs from “turtle watches” are 100% no-go for me. Most thick lugs are no good, straight and pencil-thin lugs are also not optimal (Nomos Ludwig or even some Breguet)