It takes a lot of time to implements fast/robust/scalable sockets. However this is not true with websockets. With websocket you don't have to play with various

It takes a lot of time to implements fast/robust/scalable sockets. However this is not true with websockets. With websocket you don't have to play with various models, OS API's and threading. You just have to interpret/format the received/sent bytes as described in the RFC. Of course, you can put any app logic over websocket, but this has less to do with the websocket itself (then we enter the word of "app servers" for which we have endless other solutions if somebody favors a certain framework)