You can assess the quality of a broker by how quickly they respond to your queries before you open an account, and afterwards. The after-sales, service and support mechanisms are crucial to your trading journey. Good brokers will provide the right information at the right time, to help you build confidence in your trading strategy.
If the broker ignores your requests or replies late, or offers you too many choices at the outset, it can cause frustration. A broker that replies with the correct information quickly, will speed up your learning process.