That's all good, telephony works more than not, BU...

That's all good, telephony works more than not, BUT such things enrage:
- switching of call scenarios only through support. Especially when you need it urgently. Instead of working, you must call support. I have about 10 calls in two weeks
- support work schedule. Especially based on point 1, if you have an urgent replacement of a fighter - no one will switch your phone after 18:30. If something breaks down at night, and you work 24/7, no one is interested. Wait for the morning.
- Reaction to business stops. If something is broken globally, you will only know about it by a busy telephone line. Timeline for a decision? Well, try, call.
In general, as a partner of a small private entrepreneur - everything is fine, cheap, reliable. As soon as the scale appears, everything is not so rosy. And the problem lies in the processes, not the people.