One of my pet peeves from pre-pandemic commuting days is people who travel by train, alight with everyone else at the terminus, get right up to the station gateline - and only then realize they need to come to a dead stop, rummage in their handbag, pocket, or worst of all their backpack, to find their ticket or smartcard in order to get through.
To be fair, my observations suggest this is not as common in the busiest part of the peak (presumably mostly regular, daily commuters here), but worst in shoulder peak times, when trains are still busy but it's more likely that 'ladies of a certain age' will be off for an outing in town, or a dopey-looking student is wandering reluctantly into college engrossed in their phone.
My maximum annoyance, however, is reserved for bus travel (there are multiple gates at the station). In this case little old ladies will be waiting five minutes or more for the bus to arrive, insist they get on first, then realise they need to find their smartcard pass inside their purse, somewhere in their handbag - all the time blocking the validator and preventing everyone behind them tapping on.
Top Tip: You know you're getting on a bus - find your bloody ticket whilst you're waiting for it to arrive!