I've been following this website on how to deploy to Heroku. From other pages, I see that the command 'heroku ps:scale web=1' scales the app to one running dyno. However, what happens if you do not run this command? Does this mean that you have no dynos? Can your website even run or does it just run slowly/badly? How do you tell if you've set this parameter?
Depending on your order of operations, Heroku may or may not have automatically started a web dyno for you. Verify this with heroku ps.
If you don't have any running web dynos, your site will not run at all. It'll return an H14 "no web dynos running" error.