&quot;The very slowest people&quot; are actually the majority: the elderly, the very young, the temporarily or permanently disabled- if you put all of those people together they&#x27;re many more than the young, strong and fast.<p>What&#x27;s more important, each and everyone of us, will inevitably, at some point in their lives be very young, elderly or disabled. In fact most of us will probably be each of those things during our lifetime.<p>So it&#x27;s not so much a matter of efficiency as accepting the fact that human beings are not born with wheels, but with feet and that they should always get priority, despite any misunderstandings about what the purpose of &quot;efficiency&quot; is in the first place.