The label is the marketing. The rule is the product.
01
Value, quality, momentum are ideas. Nobody sells you an idea. They sell you a rulebook that turns the idea into a list of stocks, and two honest rulebooks off the same idea can disagree on a third of the portfolio. You are not buying the factor. You are buying somebody's definition of it.
02
The detail is not a detail. Change which price the rule reads, nothing else, and three points a year appears out of a factor that has been studied for thirty years. The construction choices nobody puts on the brochure are doing a lot of the work.
03
Three questions before the return number. Which metric decides cheap. How old is the data it reads. How often does it rebalance. If you cannot answer those three, the word on the tab is the only thing you actually know.
Two funds can wear the same word and own different companies. The word is what you were shown. The rule is what you bought. Only one of them decides what lands in your account.