"I am making ENOUGH money" is important, and different for everyone, but it's not enough to retain top talent. There will always be someone willing to throw more money at a great employee. Basing any retention policy on salary (beyond making sure the salary is "enough") is doomed to fail.
For startups, equity is a big motivator, because the employee has some level of control over how the company does. This allows the employee to dream of the perfect beach house somewhere, that if they work hard enough, they will be able to get. Even selling that dream isn't enough to keep the best talent. There needs to be a good team in place, and tasks need to be delegated in a way that employees are constantly challenged and rewarded by being able to build awesome things. If those aren't in place, no amount of equity or salary is going to make things better.
For startups, equity is a big motivator, because the employee has some level of control over how the company does. This allows the employee to dream of the perfect beach house somewhere, that if they work hard enough, they will be able to get. Even selling that dream isn't enough to keep the best talent. There needs to be a good team in place, and tasks need to be delegated in a way that employees are constantly challenged and rewarded by being able to build awesome things. If those aren't in place, no amount of equity or salary is going to make things better.