One thing I've seen trip up solo founders specifically: premature optimization of processes, not just code. You start building elaborate dashboards, automation workflows, or reporting systems before you even have 10 paying users.
The same Knuth principle applies to operations. If you're spending time perfecting your CI/CD pipeline when you have zero customers, that's the operational equivalent of micro-optimizing a function that runs once a day.
My rule: if it hasn't broken or slowed me down twice, it doesn't need optimizing yet. First time is a fluke, second time is a pattern worth fixing.