What reasons are there for inconsistently rearranging the interface?

I am frequently very annoyed by Google:

I google something, and then I want to view Images of that thing, so I click the second button under the search bar out of muscle memory... except often it can be Shopping, or Videos, or something other than "Images".

Why does Google think it's a good idea to "randomly" rearrange their interface like this?

I just wonder if anyone on the planet appreciates this UX choice, or if there are business incentives to doing it and trapping users on pages they didn't expect to land on.