Because so far the OPEC production cut is all talk, no action. This story discusses the fact that OPEC’s March production was increased, and that thus far it doesn’t look like the April production has fallen.
For me this story also raises a question. The EIA weekly survey of US gasoline inventory moves oil and gasoline markets. Why do the markets pay it so much attention at this time of year? We always have this problem in March and early April now that we have seasonally different winter and summer fuel blends and have to deplete the inventory of the winter fuel. March has been the month of tricky inventory balances for a decade.