He has one major flaw that drives me crazy.

他有个大缺点，让我难受发疯。

youdao

Physically fearless and noble without limit, he has only one flaw: He knows that he is a great man, and refuses to pretend otherwise.

WSJ: 'Coriolanus': Nothing Plebeian About Him | Shakespeare Theatre Company | By Terry Teachout

By contrast, Mr Eisner's flaw (he has plenty, but this is the one his biographer points to as his downfall) is his meanness.

ECONOMIST: Hollywood memoirs

"Michael has one flaw in my view that there is hardly a weekend that he hasn't been off the road at one time or another and sometimes several times because he stretches the elastic a tad too far, " said the 67-year-old Scot.

BBC: Michael Schumacher and the Ferrari prancing horse emblem