Software getting recreated, sometimes without the security promises (linux containers as they started vs. solaris zones) the previous solution had. To be fair, Google didn't really need the security in linux containers, they didn't run multi-tenant workloads, so it wasn't their top concern when submitting code to the linux kernel...

We like building new things, from different angles, but in the end it seems like everything cycles through the same ideas.

Completely agreed. It is hilarious because we all preach "don't reinvent the wheel" at the same time that our interviews are basically "can you implement this ridiculously low level wheel" on top of "come here where we are simply using the latest rims!" :)