No! As long as you take care of your bouncy castle blowers, keep them protected from dust and debris and store them out of cold, damp places, they should be fine! However, please remember to have your units PAT tested at least annually when your inflatables are being inspected.
Please remember it is best practise to inspect your blowers before and after every hire for damage to the inlet and outlet guards and also the electrical connections and power cables.
If in doubt please have your inflatable blower checked by an electrically competent person.