The thrust reverse component in engines is one of the most expensive parts of a engine.
Also, maintaining thrust reversing parts is very expensive, and quite difficult to maintain, and it DOES add to the engines cycles. They need to be maintained quite often, and a I said, it takes some time.
So, if there is no need for thrust reversing, its not used. It saves lots of time and money.
Really, a plane can land at an airport without using thrust reversers. The average runway length of an airport is usually enough. But again, it depends on the airport.
Many places now, they are starting to use Idle thrust reverse. It is not effective as thrust reversing, but it is time and money saving.
Once, on a DC-10 when we landed at DEN, it touched down a bit late, so we used full thrust reverse, and boy it was loud!
Gosh I love thrust reversing.
"Generosity is giving more than you can, and pride is taking less than you need." - Khalil Gibran