Did you coin this phrase on your own?
I guess not.
http://www.rexchimex.com/2017/04/near-success-syndrome.html?m=1https://www.rymstarayekwu.medium.com/near-success-syndromeCould this be termed "Near success syndrome in trading?".
Are you or Do you know someone with a similar episode?
If he was really that close achieving the goal then it should have been that syndrome but if not I think that was just some sort of no plan B or something or does not implement a stop-loss even if it's just on spot market. I think I know one and that's my past self but I did grow and now I always stick to my plan and there's no way perfect on trading you really can't buy at the very top or bought at the very bottom but if you devise some plan that be happy if it will be executed.