A rate limit is the maximum quantity of messages per second (MPS) that you are able to send.
Similar to the need for a speed limit on a highway, an overall speed limit for the messaging highway ensures safety and reliability. Our default rate limit is 1 message per second. This is the speed limit; you cannot go any faster. If you attempt to go faster, we’ll ask you to slow down to the assigned speed limit.
For example, if you have an account-level 1 message per second rate limit, you are able to send up to an average of 1 MPS on that account.