Engineers are particularly bad on this front. I've seen teams blow huge amounts of time building massive, distributed, fail-over systems, because that's what Google does. Even though the load could be handled by a couple of dedicated boxes, and existing customers are screaming for crucial functionality.
Scaling is a problem you deal with when your growth rate says you have to -- not when your servers are sitting idle, waiting for a sudden rush of customers will come any day now.
There's nothing wrong trying to learn as much as you can from a bunch of smart people, but that's not the same as copying the things that they've done because "it worked for them and they're successful now".
Statistically speaking, your company is probably a lot smaller than Google, and you have very different problems than Google does.