I have yet to find any "one true solution" and there is no substitute for good judgement. Unfortunately good judgement comes from experience. And the experiences we learn the most from often come from bad judgement.

I have a parable I'll pass on that I got from a mentor at my very first IT job getting out of college.

"Make three envelopes"

A new DBA arrives in a new job and is asked to come up with a rush report to determine what is the cause of all the problems with the current system. The old staff not being available because they have "been helped to find other employment opportunities". Ready to pull his hair out in panic and frustration he opens his desk to find only three plain white envelopes with the instructions "Open me first", "Open me second" and "Open me third."

He opens the first envelope and in simple block letters it says "Blame all the problems on the outgoing service team. This will buy you six months." He talks to his supervisor and does just that. The supervisor is happy, it having confirmed that he was indeed correct in firing the previous, obviously incompetent, staff.

Six months goes by and, while things have improved, management still wants more performance. At his wit's end the DBA remembers the other two envelopes and he rushes back to his office and opens the second. Inside, "Recommend significant hardware improvements. This should buy you at least another year." He goes back to his supervisor with the news and the company does indeed proceed to throw more hardware at the problem over a period of a few budget cycles.

Now performance has significantly improved but the demand comes out for still more performance as the database isn't keeping up with the increased demands. The more it does the more that is demanded of it. By now the DBA knows that he has a magic lamp with a genie who has saved him before and he rushes back to his office and rips open the third envelope. Inside it reads...

"Make three envelopes."