Unknown perspective on the passage may be critical – This probably shouldn’t come through lack of good exegesis and study, although it might. So let’s think about that first, then come at it from another angle.
Good preparation should involve not only good accurate study, but probing study that comes at the passage from multiple angles. It is good to think through how people may misinterpret it, or mis-hear you. It is good to ponder the various theological and philosophical positions in your group of listeners (even if they don’t know what their theological and philosophical presuppositions may be, you should have a fair idea!) So while it may take only so long to grasp the meaning of a passage, let’s study for so long plus a bit to ponder the potential alternative perspectives, even if the alternative is built on a flawed approach or biblical background.
Another approach is to proactively pursue varied input from others before preaching. Having grasped the main idea of the passage, offer that to others and see what they do with it. Hear the perspective of others. You can do this with commentaries, of course, but why not go for real humans too. A friend who knows the Word can be a real blessing, but don’t overlook interaction with someone who seems to be less informed. The interaction with one or with a purposely-formed group can be so significant. Better to hear that you are off target, or shallow, or misfiring, before you stand and deliver.
So the issue may be one of exegesis, but as we’ve already hinted, it could be with reception too. You may fully grasp the import of a passage and get the meaning very accurately. But how will people misunderstand the message? This is why we cannot prepare a perfect message in the solitude of a study. We need some interaction in general, and it wouldn’t hurt before this next message. It isn’t just accurate exegesis that you pursue, but effective communication to others. Their preconceived notions can be massively significant – if you know them ahead of time.