Throwing your heart into something is great, but when any one thing becomes all that you stand for, you're vulnerable to an identity crisis when you pivot to a Plan B.

Your career is your business.

In regards to planning your career, you need to treat it (your career) just like a business.

Walking on a road without seeing and planning for what's down the road will almost certainly catch you off-guard and may turn out to be a harsh blow, sometime or other.