You are responsible for all your success and failure.
That type of integrity will need to manifest in how you handle money - your money and your client money - your investments and your trades.
Until you backtest, you don't know your numbers. You need to know the expected value of a trade. You need to know what the probability is of your risk of ruin.
You can't get this without a simulator or backtesting software. If you have talked yourself into the Johnny Cochran logic of "If it doesn't fit, you must acquit," (no basis in law) you have sold yourself on an outcome that is not based on 100% integrity and is not a 360 degree outlook.
Your success as a trader will come from your knowledge of yourself - what you know, what you think, and how you feel.
You have to own everything you do and that includes all the results of the trades you take and the ones you don't.