Originally Posted by
woodway
Why does it matter which side you spin as long as the wheel is seated and everything is tight when the lever it closed?
The problem is that many people close the lever first and just use it as a handle to tighten the skewer. They don't get the full tightening that comes from closing the lever after tightening the nut.
Most higher level mountain bikes now come with thru axle wheel attachments that avoid the whole quick release process and provide a more solid and secure attachment.