The number of requests that network resources such as web servers can simultaneously serve is limited. In addition to the server's capacity limit, it has a bandwidth/capacity that connects the server to the internet.
Typical targets of DDoS attacks include any business or organization that relies on providing online services. With DDoS tests, it can be determined to what extent your systems are protected against attacks.
In addition, if a product is used to protect against DDoS attacks, the performance of the products can be determined with this test.