I don't mean discredit other's opinions but here is my take about stop loss.
If your trade lots are 'properly sized', you may never need a stop loss.
To avoid a debate because systems are different per trader, here's a thought experiment which some of you may relate to. How many of your trades have been 'supposedly right' only had it not been 'stopped'? Another one is, how many times have your accounts 'should have been blown' but saved by 'stop loss'?
If you quantify this correctly in terms of profits, then you will know objectively whether your system needs a stop loss or not.