There are two types of questions. The first kind allows you to gather information. They let you get factual data from the person you are asking it to. They are easy to answer if you have the information, and they let you keep the flow. An example of that is a "yes/no" question: "Do you have all the information you need?".
The problem with those close-ended question is that they don't allow you to deeply understand the other person. They are great at giving you quick answers but bad at letting you know the global picture. They are also terrible if you want to have a meaningful discussion with anybody. Imagine talking to someone and having that person bombarding you with them. It would feel very awkward at best, and not enjoyable for any side.
The other kind of question are open-ended ones. They require meaningful thinking before being able to answer. It's not about giving out facts one after the other, but rather requires the other one to pause and comprehend before answering. They shift the control of the dialog as well. If we go back to "Do you have all the information you need?", an open-ended way of asking it would be "What other information do you need?". That would require the person to think about what is missing.
So are closed-ended questions bad? I don't think so. They allow you to prob and build an understanding before going deeper into a subject. They let you fill in gaps of knowledge you have by being focused. However they won't let you uncover what's behind those answers.