I just don’t understand why, if there is only item, people still feel the need to make it a bulleted list. It’s Powerpoint madness! People just mindlessly sticking to the template they have been handed.
Also, if you do have multiple bullets in the list, either make them all full sentences (and punctuate accordingly), or make none of them sentences. And for god’s sake—if it’s not a sentence, don’t put a period at the end!