Why combining flask with apache2 server is better?

Question

A recent flask application I wrote needed to be on an apache2 server. I successfully completed connecting apache and flask but I still wonder why using apache and wsgi is better than just saying "python main.py" and just running the server on port 8080 with port 80 forwarding to 8080?

Answer 1

If you run your sever directly with python on a port, using Flask, then the server will be single threaded with your requests. Your performance will suffer.

How many concurrent requests does a single Flask process receive?