think Matt of razor empo posed the same question in his review video of 6c/6s. So you are not alone . to me it’s great to have an adjustable razor. Comes in handy during multiple passes, or if you have a raw face due to weather or mis adventure with feather and dry piece of crap soap the previous day and all you want is a touch up shave with a lower number or if you shave your head with a different number, or may be another family member wants to share (huh ?) Any number of reasons. it’s like having 6 razors with varying blade gaps! the gap adjustability is good to have when you are are trying out blades of different sharpness.