I will wear t-shirts and shorts in the summer around my local area, but never no gloves. Your body almost always manages to get a hand on the ground in a low speed fall...read on. Gloves are NEVER optional, like over the ankle boots they are of vital importance. (We won't get into a helmet debate).
Why are gloves so important?
..If you drop or fall off a slow moving bike your body will instinctivly put out a hand or hands to protect the head and vital body parts. Always, without question. It's a completly reflex action. If you come off a bike at high speed the body will attempt to put a hand down, but because of the speed it may or may not be successful. If you are not wearing even short, rodeo style gloves, in a slow speed accident, chances are your palms will be lacerated, as will your fingertips and fingers.
The fingers are very delicate, not being able to use your hand(s) for weeks because you were not wearing a pair of gloves seems completely pointless to me. You know I trail bike a lot, have you noticed every trail biker wears gloves? That's because we expect to fall, and we realise the palm and fingers are likely, 9 times out of 10, to make contact with the earth. If you had ever seen the palm and hand of a rider who has come off without gloves on...trust me you would be saying gloves are VITAL not optional mate.
In a high speed accident the hands are often being thrown about like weights on the end of a rope. They slam into the ground, they drag, they get stuck under a sliding body. But a pair of gloves will lessen the damage by quite a degree. Armoured sports bike gloves will also protect the knuckles and wrist bones. (Not that I wear this style of glove myself, I just wear those tan colored rodeo gloves, but they have saved my hands trail biking countless times now.)
I know guys and gals who have come off on the road without gloves, strangely enough they all wear them now, even in the summer. Additional note: It's best not to wear rings or jewellry on the fingers or wrists, even under the gloves. The rings and bracelets can get caught as you slide along and also cause damage. Heat transference being a major problem. The fingers often swell up alarmingly, and it's possible a ring or a bracelet will restrict, or even cut off vital blood flow.And for those of you who question why I worry about gloves if I ride around the local area in shorts and t-shirts...it's simple...your arms and legs will take a lot more abuse than your fingers will.I've come off on the trail in shorts before and not even scratched my knee, but the left glove was badly lacerated, I was riding slow, and so my hand went out as I fell, to save me. Had I not been wearing the glove I would have had a badly slashed hand. Having a bad slash on the outer thigh is not such a huge problem, it's a big piece of muscle tissue, it will take lots of abuse. As will the shoulders and biceps. But the same slash that is inconvinent on a thigh or arm becomes a massive laceration on the delicate structure of the hand.
Anyone reading this from a military background will understand what I am talking about.If you are in a firefight (a shootout with enemy forces) and you are wounded in the leg, although you cannot stand or move around properly you are still able to fire your weapon. If you are wounded in the arm or the torso you may not be able to fire your weapon, but you could probably still reload yours and hand it to someone else. You could take over the radio, perhaps tend to another wounded comrade. BUT...if you have been wounded in your hand (s) you are unable to do anything in the combat zone except observe and call out warnings to your fellows. This is called being Combat Ineffective. To all intents and purposes you are rendered useless as a fighting soldier.
I have noticed that in the last few years many professional soldiers are now wearing gloves. Some are kevlar lined and flame proof. They have obviously realised the importance of protecting their hands and digits also.
Another Jaq-Tip here...
Short summer gloves, stuffed into your helmet when you walk around, can easily fall out. I've had it happen to mine often.
Taking a page from American rodeo riders, ranch hands and some USA bikers; I now shove the wrist part of the short gloves inside the waistband of my jeans and fold the fingers over my belt buckle.
I have not lost a glove that way yet.
I have lost or dropped them by stuffing them in my back pocket, they tend to fall out when you sit down/stand up.
A last thought to ponder...
Think on this...if you damage your hands badly enough in a bike accident:
A: You won't be riding the bike again any time soon.
B: You will not be able to use a toilet without someone to help you.
C: As many today are in the IT business or use a keyboard frequently; well you won't be doing that either.