There’s has never been a publicly renowned rubber-stamper. Yes-men do not have songs of praise written about them. Brown-nosing your way to the top is not often a good approach for long-term success. At some point, you will have the responsibility to be the bad guy.
As someone responsible for making decisions, you will sometimes be handed bad ones by the people in charge. Sometimes you will have to go along with those bad ideas whether you like it or not. Sometimes you must speak up and say no. Knowing the difference is called politics.
Challenging the decisions you are asked to make does a few things. First, it teaches your team that they have to think through the decision before they bring it to you. If you ask them questions they aren’t equipped to answer, they weren’t ready for a decision to be made. Second, it shows that the decision process has at least some rigor to it. People will learn that bad ideas will be challenged. Finally, it forces you to think through related aspects of the decision. Any given decision is not made in a vacuum, it can have trickle down effects.
Making decisions is why you get paid the big bucks. Respect the process and do it right.