The Vienna talks went largely according to the script: the Saudis and Iranians at loggerheads, meaning any agreement was wishful thinking
The failure of the once mighty oil cartel Opec to reach a production-curbing deal was hardly a big surprise. Saudi Arabia wanted to limit output in order to underpin crude on global markets, but for both financial and political reasons there was never the remotest possibility that Iran would agree.
No longer a pariah after the lifting of western sanctions, Iran is keen to ramp up its production. Clearly, it would prefer oil to be changing hands at $60 a barrel rather than $30 a barrel, but $30 a barrel is a lot better than $0 a barrel. Both Saudi Arabia and Iran want to be regional top dog in the Middle East. There is no love lost between Tehran and Riyadh.
Related: Opec fails to reach agreement on oil production levels