Members of the oil-producers group known as OPEC+ have tried to push crude prices upward with unexpected supply cuts since last year. Wall Street isn’t yet convinced that will pan out.

On Thursday, a million barrel-a-day pullback surprised a market that had largely anticipated that the cartel and its allies would hold output steady. Crude prices seesawed after the announcement, ultimately slipping to their sixth-straight weekly drop, suggesting many traders were unsure if it was the surprise they wanted.