Meaning of be one's own worst enemy in English:
be one's own worst enemy
phrase
Act in a way contrary to one's own interests.
‘I try my best, but he's his own worst enemy’
- ‘Hitler went from being a superb strategist in the early part of his rule to being his own worst enemy later on.’
- ‘Not for the first time in my life, I had been my own worst enemy, but if people don't treat me correctly, I have to hit back at them.’
- ‘But you can be your own worst enemy when there's a lot of negative chatter going on inside your head.’
- ‘I think a lot of the time I can be my own worst enemy.’
- ‘The team were their own worst enemy as they squandered numerous chances in a nervous opening game.’