[gshx]

Agree and that's a great point about human failover. It can become a challenge for distributed databases running on a large number of instances (like bigtable) but if we're talking only about master HA, then yes, that can still do with human intervention though automation is still preferable. For smaller db setups, much easier to just let a human/dba intervene.

[mrkurt]

Smaller DB setups rarely have the ops/DBA support required to do manual failover. I think having an as-consistent-as-feasible, automatic failover is something of a default expectation for databases these days, at any size.

[Xorlev]

You need a larger team to do automatic failover because getting it right is a massive PITA. Either that or pay someone to do it right for you, e.g. RDS, managed solutions.

Manual failover is often a lot safer, automatic systems have a nasty habit of not doing what you expect them to and trashing your database / losing data.

[gshx]

I should have clarified that I meant small in the context of less scaled out and more vertically scaled like the traditional rdbms running on big iron.