I suppose because you hands get cold ?
I feel more comfortable wearing gloves winter and summer and have some lovely light grey, and light weight, RAF issue flying gloves. They keep the draught off my right hand in particular but overall insulation is not the real objective. In my view coupled with the leather rim Mota Lita they increase feel and the overall experience. In summer if wearing shortsleeves I tend to use RAF issue gauntlets made of the same fine supple grey leather. Probably just a frustrated would be Lightning pilot!
Andy