[AndrewC]

Wind and a little time turns sandstone into arches that resemble flying buttresses. It does not follow, to many people, that more time using the same process will result in the formation of Notre Dame Cathedral.

Sandstone arch image

Flying buttress image

Notre Dame Cathedral image

[Ichneumon]

Wind and a little time turns sandstone into arches that resemble flying buttresses. It does not follow, to many people, that more time using the same process will result in the formation of Notre Dame Cathedral.

That's because "many people" fail to take into account why a process which includes variation, reproduction, and selection is very different from erosion, and is capable of much more.

If you're going to make an analogy, make sure it's a valid comparison.