article

if diverse team is to perform successfully, it must develop trust and cooperation.
what is the wrong with this sentence.

Him

You need an article before ‘diverse team’, either ‘a’ or ‘the’. If this is meant in a general sense, ‘a’ would be preferable.

Alan

is it correct?
“if diverse teams are to perform successfully, these must develop trust and cooperation.”

You forgot the capital letter at the start of the sentence.

In this sentence one would normally say " … they must develop …".