Full-fingered gloves – as opposed to mitts, that is – make sure that your hands stay warm enough to shift gears and, more importantly, brake.
Now gloves are quite polarising full stop. Personally, I prefer to not wear glovess whenever possible but outside of summer it’s often just too cold and you need to cover those fingers up.
But autumn gloves are generally rather different from winter gloves, because they’re thinner, less insulating and, as a result, more flexible. For example, Galibier’s Roubaix Vision III gloves are a perfect example of an autumn glove. They cover the whole hands, have extended cuffs to fit over the ends of arm warmers/under sleeves but they’re not padded out with scores of bulky insulation that would make them far too hot when the temperatures aren’t in the low single figures.
Another feature that’s useful in autumn gloves is grip on the palms. Given that autumn generally brings a fair amount of rain with it, grip that makes holding onto the bars and getting purchase on the brake levers a little easier will be a big bonus.
To be honest, if you don’t feel the cold you might not even need gloves in autumn, but it’s always best to have something in reserve for those occasions where they’re necessary.