There are many reasons a flight is cancelled or delayed. And there are many solutions to help you get to where you are going.
Weather delays. Probably the biggest reason most airlines are delayed or cancelled. Bad weather can cause havoc for flying. There are a few things you can do:
If the forecast is for severe weather at your departing airport, arriving airport or connecting airport. Call the airline you are traveling the day before or day of and ask if you can change your ticket to avoid the weather. Most will allow a one time change for no charge. You may be able to get routed another through another city. ASK ASK ASK. It may save you a lot of trouble and getting stuck at the airport.
Maintenance delays. If the pilots call for maintenance, there is a reason. It is to keep you safe on the ground. There is no pulling over to a Texaco in the sky! So you must have patience. Some delays are very quick and so very lengthy. Sometimes the flight will cancel and sometimes you will have to change aircraft. No matter, your flight will be delayed. This is within the airlines responsibility, and they should give you a hotel if you must spend the night.
Security delays. TSA (Transportation Security Administration)
Customs (US Government Passport control)
You must go through security to get on a flight. The lines can be very long. If you miss your flight due to Security, most airlines will not pay for an overnight hotel. They will try to book you on the next available flight.
Flight Crew delay. Staffing an airline can be very difficult. The flight crews change planes just like the traveler. If one up line flight is delayed it may impact your flight. Also, flight crew have time limits for safety reasons.
This is in the control of the airline. Most airlines will put pay for an overnight stay. The airline will try to get you on another flight.
As you can see, there are many reasons for flights to get delayed or cancelled. Most airlines do a reasonably good job of managing things. If something does go wrong then pro-active. Call the airlines reservation number, go on line to the airline web site. Wait and talk to an airline agent.
ENJOY THE JOURNEY !
IFR