I don't think you need a reason to invest. You should be making more money than you spend, so you might as well put the surplus to work.

Be careful here. You should have some "rainy day" savings. You should have some retirement plans. You can save for big items like a vacation.

However you don't know how long you will live. Don't be a miser who spends nothing. If you have surplus after the above you should either spend it or donate to charity.

Okay