SQL server, query taking 24 minutes to run on a good day, when going down hill wind assisted. Made a few small alterations and got the query running in sub 1 s

SQL server, query taking 24 minutes to run on a good day, when going down hill wind assisted. Made a few small alterations and got the query running in sub 1 second. Boss had to have the code vetted 3 times because he could not believe it. You have to take into consideration that it was originally written by an absolute muppet, and then altered by an `database expert`.