How much maintenance you’re willing to do may be a determining point in which hardscape product you use.
Here’s a general guideline of materials and upkeep:
Composite Wood
Need to be washed annually
Concrete
A sealer should be applied about 6 months after the foundation is put in and every 2-3 years after so it doesn’t get discolored or stained.
Flagstone
No sealing required.
Unless they’re in concrete the stones need to be checked in case they’ve moved.
Natural Wood
Inspect annually for rotting, splinters and loose screws.
Power wash and seal annually to help prevent discoloring.
Pavers
No sealing, painting or staining is necessary.