How can I deactivate the "Most Likely" Forecast Category?

Hi all, 

I'm currently configuring Forecasting and want to remove or deactivate the "Most Likely" Forecast Category

 as we don't plan to use it in our forecast process. 

 However, when I try to deactivate the value, I get the following error: 

Cannot delete this value. This picklist must have at least one value for status category "Most Likely". 

Right now, no Opportunity Stage is mapped to "Most Likely", but the system still doesn't let me remove it.

Has anyone successfully worked around this? 

Thanks!