Why is shorter better?????

This is the fight I have had with developers for years. They provide the argument that "ThisIsTheProductionDatabase" is too much typing, so they name it "PD".

Same thing for objects. Actual words usually work best for names. There is never any confusion.

With your prefix "sa", when I look at this, I would expect some sort of DBA utility database.

In the SQL Server world, SA means system administrator, not 'Staging Area".

How many times have you had to provide an answer, verbal or written, as to what these arbitrary and meaningless prefixes mean? Add up that time, and then multiply that by your salary. These poor practices cost an awful lot of money.