It’s a bit of an uneven piece, but Peter Krmpotic’s What’s the Secret to Becoming a Great Product Manager? makes some good points about ego vs. customer focus:

The ultimate goal for product managers and product leaders is to instinctively focus on the customer and not their own egos. This is hard since it is natural to be self-centered and unnatural to be customer-centric.

In Scott Belsky’s recently published book “The Messy Middle”, he highlights how we are hardwired to prefer short-term rewards, because delayed gratification causes anxiety and discomfort. Thus, I think the main career-long objective for product managers is to reprogram themselves over time from being self-centric to customer-centric, to get the urge of acting on their own ideas out of their system. Or as Belsky puts it, “to hack their reward system”.