Should a technical founder let the code go?

I built a SaaS from scratch alone. Now I have two junior devs and two mid-level devs on my team. Their code is usually OK, but I feel that they don't think about the big picture very well. Usually, they don't write enough tests, there are some performance issues, and sometimes they don't make the best architectural decisions.

I think they are nice developers, but they need more time and experience. I have been trying to coach them, and I can see some real progress. However, I'm exhausted from personally reviewing code for four developers.

I feel that to keep the business growing, I need more time for marketing, sales, legal, and everything else. However, once in the past I led a tech team that failed completely because we assumed a code base that was almost impossible to work with. That led to bugs everywhere, high turnover on the team, and it basically killed the product.

So, should I let the 'does the job' code be approved and deal with the consequences in the future, or keep pushing for better code quality now?

Has anyone had a similar experience?