A lot of companies choose not to do process oriented work, and just wing it instead because they believe they can go faster. That's fine. It's a choice driven by resources.

What's not fine is complaining that someone you hire is "bad" because they get stuff wrong when you're forcing them to work without a process-based safety net. People will always make mistakes. If your belief is that everyone should be perfect because you've chosen the no-safety route then you don't get to complain when someone nearly sinks the company. Expecting people never to get things wrong is unreasonable, and it's the exact reason why we have processes to catch problems.

Focusing on process and making the safest process will kill your team. Your best team members don't want to be hampered by a process that slows them down to protect them from their worst team members. The advantage you have as a startup is speed, don't throw it away so easily.