It all depends on individual airlines, and it varies depending upon the time ticket is being cancelled. Nearer to travel date cancellation charges are always high. Some airlines like Indigo offer flexi fares, where they charge an additional cost to the flight ticket and give you an option, that in case you reschedule or cancel the flight, no or less cancellation charges will be deducted.

In most cases, for cheap flight tickets it does not make any difference. They keep the "change fee" almost same as "cancellation charge". Though some airlines offer attractive change fees compare to cancellation fees.