Are drop-catches and stumping-failures recorded for official statistics ?
This type of records will help in knowing who is a better bowler, in a bad team of fielders or wicketkeepers.
Eg : Consider a very good bowler B1, who can easily fool the batsmen so that the wicket-keeper can stump-out or catch-behind; but the wicket-keeper is not "talented", so the batsmen escape. Also, bowler changes his pace such that fielders can get catches easily, but they drop most of it.
Consider a very bad bowler (or an average bowler) B2 with a great wicket-keeper who never misses opportunities for stump-out or catch-behind. Also the fielders are too good, such that they stretch and jump beyond reasonable limits to convert sixes to caught-outs.
When the records are compared, bowler B1 will look very bad, while bowler B2 will look very good. To high-light this type of issue , records (statistics) of drop-catches and stumping-failures will be very helpful. Eg For making "World XI teams" or "Dream teams".