To signal that you are seriously into collecting without flashing serious money. Something no one else would truly appreciate but another collector? For me, it’s vintage 50’s thru 70’s and perhaps a polerouter, an enicar, or maybe a bubble back. Nothing expensive.
And you? The rule here is it can’t be something that a non collector would know or that costs more than 10k (no Journes, or Daytonas) and it has to be something that would immediately give you away as a collector as opposed to someone who went to an omega boutique
With Instagram many non collectors buy. The game requires that another collector can identify you as a collector with certainty. Sure you might get the 1/1000 wearing hand me down, but leave them aside, they will be rarer than the watches they wear.