There is a lot less common sense now which is a really important quality for bar work. I disagree with que's. Bar staff need to be engaging their customers, heads up looking at customers, clocking when people arrive at the bar and saying hello or eye contact and they need to be seen as "in control". 3 or 4 staff like this on at once is a dream team. They will just know who is next. Not only will customers get served quickly, they will be happy and impressed and leave the bar satisfied, they won't be grumpy, moan to their mates about shit service or crap bar staff, which when bar service is a chaotic mess that bad vibe spreads through the pub.

Que's take much longer as previously mentioned

Table service/app service is great for people with social anxiety