First, consumables trap. Low-quality UV ink, water-based ink, and solvent-based ink will slowly murder the printhead.
Second, operational pitfalls. Do not cut power directly before shutting down. Do not shut down when there are other jobs waiting to print. Do not ignore ink level checks. Do not ignore the status of the UV lamp. Do not ignore nozzle test prints. Do not ignore platen flatness checks. Do not ignore ink purge checks. Do not ignore the ink supply lines and the printhead itself.
Third, printhead parameter settings. Crash protection set too high. Negative pressure set incorrectly. Air leaks in ink tubes, butterfly filters, or valves. Excessive dust in the environment.
Fourth, purchasing scams. Beware of second-hand and refurbished printheads. Check the serial number and manufacturing date, inspect the appearance and materials, and perform functional tests.