Another aspect is the cost and risk to the company if it ships defects to production (assuming it actually has customers, has largely de-risked product-market fit, etc). Suppose a company is in the hardware business and locks its cash into building and shipping a run of their v1 consumer product, then discovers after shipping there's a defect in the entire manufacturing run that means the product needs to be recalled and repaired. That's likely sufficient to bankrupt a young company that doesn't have revenue flowing in from other products or lines of business. You'd want to be doing a lot more QA than merely unit testing.
The answers here are all correct for the use case of the person answering it. We don't know your use case so we can't give you a good answer.
For example a seed funded health tech company needs 100% test coverage to be compliant with regulations.
A bootstrapped online collaboration tool with no users doesn't need any tests.
A seed funded online collaboration tool needs some tests so the developers can work together without breaking each others code.