A Wi-Fi router may have great hardware capabilities but the software in it degrades. Security issues are found, they are not patched in time, or the software in the router is no longer supported. Alternatives like DD-WRT are not perfect but they are above and beyond the option of settling for a poor routing experience.
No one really had to create DD-WRT, but it is great that they did. The solution has given many people greater use of their routers. DD-WRT has made router hardware much more useful for the people (security and features) wanting to make wireless connectivity a more pleasant experience. The opportunity exists to improve the environment that results in the expansion of these kinds of solutions.
Rumor has it that rules are being worked that may unintentionally ban tools such as DD-WRT. That would be tragic and while eliminating a tool in advancing the development and availability of effective network security software. Professional and residential. Hopefully, DD-WRT and other solutions of its kind continue to be an accessible standard that benefit many.