For the sake of discussion – What is most important 2 u?

So we see a ton of posts on what someone wants to do... How they ran... what's wrong...etc. When there is work to be done, and I'm talking large... like a paint job, and engine, a rear axle... What is the most inmportant and biggest factor going in?
Some examples:

Primary Usage
Ease of procurement
Source of the component(s)
Bling or Wow factor
Overall quality
Author: admin