From Management Seat Time:

“One of your jobs as a manager is to build a network with other managers and teams to get things done. You must build relationships outside your team for your team to succeed. Management success is not about what you, personally, can do. It’s about what you can get done through and by others.”

“You can’t solve problems bigger than your team without a network of friends and allies within your company. It’s important to cultivate this network purposefully and intentionally. Lot of my regrets my time as a manager come from situations where I should have asked for help and didn’t. ”

I think this is pure gold.