Let's say a time machine is invented and it can be used only one time per each individual. You can travel back in time and have your consciousness merge back with your younger self while retaining all of your knowledge and memory. -I saw it on a scifi show a few years ago-.
Would you go back and change some of the events in your life. Would you want to change some of the decisions that you made. Would you not get in a bad relationship. Would you play the lottery knowing that you would win. Would you chose a different a different career. Would you stop someone you know from dying in an accident because you have that information.
Would you live where you are now. Would you buy Amazon, Microsoft, Apple stocks and get rich.