Qatar Airways — Delays in flights

I have travelled from Toronto, Canada to Tehran, Iran. It was a 2-stop flight. When starting the flight from Toronto to London, it had more than 1 hour delay. For the second flight from London, UK to Duha, Qatar it had more than 2 hours delay. Because of these delays, I lost my last flight from Duha to Tehran, and I had to stay at Duha airport over the night. In this case, my 19 hours flight changed to more than 25 hours. This is disaster and I am not flying by Qatar Airways anymore. THIS AIRLINE IS NOT RECOMMENDED BECAUSE IT IS WASTING TIME, ENERGY, AND MONEY.