Not so sure about 3. Wouldn't it be more sensible to be flexible in terms if what you optimize? Some projects need best work, some need a friendly face, some should just die quickly.
Determining what a project needs and doing your best to deliver those needs is what "doing your best" means. If you spend months working on a solution that needs to be and can be deployed in a week, because you want to make it shiny and such, you aren't doing a great job on that work.
This is hindsight in my case, but I will say that a lot of the resilience and experience I've developed in my career has come from putting best effort into less-than-ideal or even failing projects (in my defense, in most cases I didn't know they were failing or in a bad state).
