Is Vertiv Stock's Fall A Bargain Or A Warning?

Vertiv (VRT) stock has fallen 15% from its September 8 high. A $10,000 purchase at that high is worth about $8,500 today. A fall like that makes you want to act. It could be a cheaper way into a company that sells power and cooling equipment for data centers. It could also be a sign that something is wrong. Why are investors selling Vertiv.