The popular advice is that unless you are feeling unreservedly enthusiastic about something - a hell yes - you should not go ahead with it.

While this is a useful framework, I find it less useful for making a decision on whether to take up something. 

Following this framework feels like I'm outsourcing the responsibility of making my decision to a framework without understanding the underlying reasons for the decision. This outlines my long-held disdain with blindly following frameworks.

Instead, when it isn't an unreservedly enthusiastic yes, it is good to take a step back to reflect on what's causing the hesitation and to address those head on instead.