The Type of Motorcycle Jackets do Matter
For summer, riding in a mesh jacket will let air through to keep you from becoming dehydrated. You must wear a jacket even on warm days. The jacket should have armor for the shoulders, elbows and back. Without shoulder armor you can tear your rotator cuff if you slide.
The sizing of the jacket is important. Better tight than loose. The wind will blow up the jacket like a parachute if the sizing is too large. A tighter jacket will not let the wind in and offers less wind resistance.
The jacket should have a snap closure in the rounded motorcycle collar. This will also help in keeping wind out. The summer variety sometimes has velcro instead of the snap. Whether the jacket is leather or textile is the rider's choice. Both will help against abrasions and should not tear. Motorcycle jackets are short so they do not catch any engine parts.
A good jacket will also be windproof and waterproof. In winter months you do not want cold air penetrating the jacket. The sizes for every style and manufacturer differs. You might be lucky finding your correct and a comfortable size on your first try.
The jacket should have some parts with a bright reflective material. Your goal is always to be noticed by other drivers. When you first set out, make sure the armor is in the right place and has not shifted. Move it back with your hands. When washing the jacket take out the armor and remember to put it back the right way or you lose protection.