Why are questions important in collecting ideas?
Research shows that when collecting ideas it can be helpful for results and long term engagement to center your idea collection around a challenging, open-ended question.
The better the question the better the ideas you are going to collect. A good question is open-ended enough to no assume the solution but focused enough to inspire people to come up with ideas that are actually going to be useful for you. If you just collect general ideas you risk collecting a lot of irrelevant ideas and end up disappointing people because you can't use their input for anything actionable.
A great format are so-called "how might we questions", for example "How might we improve our productivity during meetings?". Many solutions are possible but it clearly points towards the problem you are looking to solve. It also does not assume that the solution is proven to work - it just might.