Let's say you have a route named my-route-mxhmp

~]# oc get routes
NAME              HOST/PORT                                          PATH   SERVICES     PORT     TERMINATION          WILDCARD
my-route-mxhmp    my-route-my-project.apps.openshift.example.com     /      my-service   8080     reencrypt/Redirect   None

And you delete the route.

~]$ oc delete route my-route-mxhmp
route.route.openshift.io "my-route-mxhmp" deleted

And a new route is immediately recreated. In fact, when there is a path (just the forward slash in this example) this is your clue or hint that there is an ingress route.

~]# oc get routes
NAME              HOST/PORT                                          PATH   SERVICES     PORT     TERMINATION          WILDCARD
my-route-chkgz    my-route-my-project.apps.openshift.example.com     /      my-service   8080     reencrypt/Redirect   None

This almost always suggests that there is an ingress route that is automatically recreating the route.

~]$ oc get ingress
NAME       CLASS    HOSTS                                            ADDRESS   PORTS   AGE
my-route   <none>   my-route-my-project.apps.openshift.example.com   /         80      4s

If you want to permanently delete the route, you would delete the ingress route.

~]$ oc delete ingress my-route
ingress.networking.k8s.io "my-route" deleted