Consider it holistically, rather than one at a time. Every company has its own footprint of "per customer" resource usage, and every company probably has unusually low aspects one way or another, but when a company comes back as "low" to "very low" for every such metric, it's time to investigate harder. Maybe they're just that genius, or maybe there's something about the company you don't understand yet, or maybe they're cheating you... the whole point of due diligence is to resolve those "maybes" into "certainlies", because they all factor in to your decisions.