There will be times when you get it wrong. Car mechanics and even doctors don’t get it right all the time and neither will you. Mistakes are easy to make and inevitable. As markets get more and more complex the chances of getting things wrong increase even more, and the longer you’re in business the more times you will be wrong.
But never see this as failure. Accept mistakes as part of life and keep on track by not feeling guilty. If you are doing everything you can with everything you’ve got you are a winner so you have nothing to feel guilty about.