There are alot of mediocre bartenders out there. It is the small details that amount to the big picture. Especially when there aren't that many moving parts to a cocktail.

The things that gets most overlooked:

Ice program; dilution rates vary on size of cubes and shape.

Fruit expressions; many drinks fall short due to the lack of an expression or thebwrong type of expression. The peel pith shouldt be too big or too small ( the oils are best expressed somewhere in the middle).

Glassware; dirty or cloudy glassware is awful. Lipstick stains💄, straight to jail.

Shaken vs. Stirred cocktails; as a rule and traditionally, cocktails with juices get shaken and cocktails with all liquor get stirred. There are exceptions to the rule, ie dirty martinis are shaken and mojitos are built in the glass. But noone should be shaking Negronis or Manhattans.

"Up or on the rocks?" ; your server/bartender should always ask this question. If you want dilution over the course of your drinks life get it on the rocks. If you want to keep the same taste and strength of your cocktail , get it up 🍸

Cheers 🍻