From my experience of boss looking at people working. Working hard is by a huge margin a lot better than working smart. Trust me I know my shit. Once I even wrote a formula in Excel! /s

That being said with experience you stop using anecdotes, easy pre-made sentences like "premature abstraction/optimisation is the root of all evil!" and you understand that there are no generic solutions and you need, every time, to think hard about the best way to produce something relatively to the context and constraints which, most of them, aren’t technical but organizational and human related.

And also, if you intend to work on a project more than 6 months. Quality is really worth it. The lack of quality works like accumulating mud. After a while, you are stuck, and the next step will require a huge amount of energy.