dig your own grave

US /dɪɡ jʊər oʊn ɡreɪv/
UK /dɪɡ jʊər oʊn ɡreɪv/
"dig your own grave" picture
1.

to do something that will cause you problems or failure in the future

:
If you keep lying to your boss, you're just going to dig your own grave.
By refusing to compromise, the politician was digging his own grave with the voters.