Retired star hedge fund manager Stanley Druckenmiller says investors should be wary because the Federal Reserve’s loose money policies have yet to come home to roost.

“I know it’s so tempting to go ahead and make investments and it looks good for today, but when this thing ends, because we’ve had speculation, we’ve had money building up four to six years in terms of a risk pattern, I think it could end very badly,” Druckenmiller said at a Jan. 18 event, the transcript of which was just circulated on Friday, CNBC reported. Druckenmiller said warning signs include a high number of initial public offerings of unprofitable companies, and high levels of debt issued without many restrictions to companies with poor credit ratings.

Some say keeping rates low has been necessary to avoid a financial crisis relapse — something policymakers failed to do in the Great Depression era, which many argue led to the 1937 economic relapse. Druckenmiller says that’s way off base, and “implied that the Federal Reserve would not cause to another recession by tightening the flow of money into the system,” CNBC said. In 1937, net worth per household hadn’t returned to pre-1929 levels, before rates rose; today wealth is well beyond pre-financial crisis levels, according to Druckenmiller. “We’re not even close to the kind of numbers we had in 1937,” he said.

Still, Druckenmiller said he was not “net short” stocks. “You have to be on alert to that ending badly,” he said. “Is it for sure going to end badly? Not necessarily. I don’t quite know how we get out of this, but it’s possible.”