Would 10 days Vipassana a waste of time, if not practised afterwards?

People who have done 10 Days of Vipassana Meditation retreat 5 to 100 times often say that from 5th day the Mind becomes very subtle & remains 24 * 7 like that. However when they're back to their families & life an average normal lifestyle. The Mind becomes similar to what it was before (in most cases, as per my experience). Is our Mind is similar to any other muscle of the body, The bodybuilders can come back in shape quicker than someone who has never achieved it before. If someone is doing the vipassana 1st time & someone else has a good experience. Would a 10 days vipassana a waste of time if not practiced after?