How Long is "A Few Minutes" in Beauty Time?

One of my absolute favourite instructions for a beauty product is on the label of Bumble & Bumble's Creme de Coco, which advises users to leave the conditioner on for not five, not ten, but seven minutes. No more, no less. I've often wondered what terrible, terrible calamity might await me if I disobeyed this instruction - would my hair fall off? Would I be left standing in heels on the train the next morning? Would Vichy discontinue their Normaderm microdermabrasion kit? Well, I have never dared tempt fate in such a crazily reckless fashion, so instead I make like Cathyfly and bring a waterproof stopwatch in with me when I shower.

(I may have made that last bit up.)

At least the bauld B&B actually bother to put a timeframe on their gear; it drives me cream crackers when products say things like "leave on for a few minutes". What does that actually mean? "A couple of minutes" would be fine, because sure that would mean two minutes, right?

But a few minutes - now just how long do you reckon that is?