Without reference to a specific question, it’s quite hard to give a specific answer to this.
It could be that you asked a question that lots of people felt able to answer, and therefore generated lots of answers without it necessarily being a particularly interesting or good question.
It could be that the discussion was good, but perhaps it was good in its own right, without the quality of the question itself particularly inspiring good discussion.
It could be, like @partyparty said, that people forget to click the “great question” button.
It could be that people are quite selective in giving “great question” or “great answer”, and that just “liking” or wanting to write an answer to the question isn’t enough.
It could be that your question was very brief, and whilst interesting, you may not have given enough elaboration to demonstrate to other users why it is particularly interesting, or perhaps, if you didn’t elaborate, others felt that the answers were more interesting than the question.
Following on from the above point, it could be that the question was written in a way that didn’t evidence the quality and depth of thought behind the asking. People may be more prone to give “great answers” because they illustrate that quality in a way that a question may have not.
I’m sure there are many more reasons to add to this, but I certainly wouldn’t assume that not receiving a “great question” means that people didn’t enjoy or like answering the question in some way.