For example, he seemed to flip flop on vaccines before his term was up. At first he made it clear that the vaccines would be optional but as he got closer to end of his term he was sending some major mixed messages about just where he stood on the issue of whether or not vaccines should be mandatory.
Same thing goes for the issue of gun control. He was saying some scary shit to Feinstein about seizing guns in a meeting with about a dozen other politicians. Which was just the opposite of his strong stance AGAINST gun control during his 2016 campaign. Hell, the NRA actually endorsed him back then.
Then of course there's the thing with Assange and also how he ordered those missile strikes on Syria based on flimsy evidence that Assad actually did what he was accused of doing.