Have you ever heard the phrase "you get what you pay for"? It is true. You do get what you pay for. But you also get what THEY pay for.
What does that mean?
When you try to compete on price and offer prices lower than you should, four things happen;
You know the customer's mindset is Cheap. The customer is looking to pay the least amount possible and squeeze as much as possible from the purchase or transaction.
Customers don't value what they get. If their mindset is cheap, they will believe what they got is worth what they paid, which means it is not worth much.
Customers won't trust your work. When someone is paying as little as possible, they are going to assume you are cutting corners, just like they are. Because they don't fully trust your work, you will find they ask for more, or watch over the project, more than a high paying customer.
People willing to invest in themselves see the world different. Someone who is willing to pay more will believe they are worth more. And they will expect your work to meet their expectations.