Surgeons are generally trained with a grueling multi-year academic and practical program about how to conduct surgery. DBAs aren't. If you're lucky you have someone who has been trained to be a DBA professionally - but I've never worked with one, all the SQL I've interacted with has been run by people with unrelated job titles who learned how to operate databases by Googling when necessary.

You're welcome to fire people if you think it's going to help. I'm just curious how you think a skilled, trained DBA is going to show up at your desk when that happens.

You pay them money :-) though think the guy that was our DBA at BT has now retired - his first boss was Diskaja at NPL labs

At a bank, yes. However, for a smaller startup firm, no. (The truth is, for most of this stuff, most of the time, it just doesn't matter.)

It just doesn't matter until it does.

Which is fine if failing is cheap. Depends on the risk profile.