How long can a floor closer / hinge last ?
Firstly, that will depend on the 'traffic' - how often the door is being utilised.
Secondly, the size/weight of the door in use must match within the limit of the capacity of the floor closer. Inevitably, a bigger/heavier door needs a bigger capacity floor closer, hence a costlier one.
Under normal usage and where guidelines are followed, the floor closer will last many years with some brands giving 150,000 to 200,000 times utilisation of the door.