There is no benefit to making up stories unless you are a professional novel writer. Most often what you are assuming is untrue and may cause lashon hora. Most of the time the subject matter of whatever you are dreaming up is none of your business in the first place. It is nobody else’s concern why your neighbors are coming out of the gym – maybe they are the landlords and are collecting the rent, maybe they were asking directions to get somewhere, maybe they are painters and are redecorating the place – maybe, maybe, maybe. You should concern yourself about your own studies, morals and ethics. Don’t make things up and don’t assume. There is a very old expression : “Never assume anything – it makes an ‘ass’ out of ‘u’ and ‘me’.”