IF you've been brought into an organization as its first product manager, most likely you've spent your first 100 days figuring out the lay of the land.
AND you've probably figured out that there are changes that need to be made in order for the product and perhaps the organization to succeed. Otherwise they wouldn't have hired you.
THEN you realize you're at a crossroads. You can either continue along the previous path, or introduce the disruptions required to get the product to the destination the organization has set for itself.
This is a very lonely moment in time. It's also the most important moment you'll face in your time with that organization.
How you lead your team through this crossroads will challenge you in every way. It's a make-or-break time for you, Mr. Product Manager. Embrace it.