In theory no, but any fault can be a major issue. The lift should be ground fault protection Shore power at a commercial dock does not have to be ground fault protected but in your case if a residential property, I would expect ground fault protection of some sort. Having protection on the shore power feed as well as the feed for the lift will greatly reduce the chance of a fault being life threatening. Remember that also applies to anything else near the vessel that you might come into contact with light lighting, receptacles for who knows what etc.