The short answer is no, but having somebody to manage HR in your business (whether via an in-house department or through an outsourcing arrangement) puts you in a much better position to be an excellent employer and attract the best talent for your business.
It also ensures that you act in compliance with the law and means that you're fully equipped and able to handle those inevitable situations which at some stage will affect most businesses, such as disciplinary and grievance  issues, handling flexible working requests and correctly managing family rights.