Why cant we become rich by investing most of our money for first 5 years, living like a monk initially?

Example: Saving too tighly and heavy investing. - avoiding going out and eating out. - spending when neccesary and unavoidable. Ex: phone broke or get stolen, so buying a new, not because you wanted that latest Iphone. - Avoid buying gadgets. - avoid spending money on luxuries. - you know the rest of such things from which we can save money. And then investing it all and living like a poor for initial years of your life. Doesn't it work? I understand expenses are unavoidable, but what if you save the maximum??