After a speed boost, very, very few taunter can outspeed Octillery/Smeargle. If you want to Taunt an Inconsistent Pokemon, you are essentially forced to use Sableye/Erufunn/Tornelos/Voltlos. Let's not forget that Taunt can miss if they get an Evasion boost. Lastly, Taunt only lasts for 2 turns...