Originally Posted by
Dave Mayer
Next solution: the thru axle! It is not actually an axle, so it doesn't support any forces and it doesn't make anything stiffer or stronger. It is merely a wheel retention device, that features less clamping force than a properly applied QR. But it is relatively idiotproof, and allows the bike industry to shed any liability.
They probably developed the thru axle because of all the folks spinning their quick releases closed. Thru axles just make good use of all that extra work.