"For some reason" is a phrase commonly used to describe a situation or action that is not easily explained or understood. It suggests that there is a specific reason or cause for something, but it is not immediately apparent.
One example of when "For some reason" might be used is when someone is trying to explain why they did something unexpected or out of character. For example, "For some reason, I just couldn't stop laughing during the serious meeting."
While both phrases suggest that there is a reason for something that is not immediately apparent, "For some unknown reason" implies that the reason is completely unknown and cannot be guessed at, whereas "For some reason" suggests that there is a reason, but it may not be obvious.
There are many reasons why someone might use "For some reason" instead of being more specific. It could be because they are unsure of the exact reason themselves, or because they do not want to disclose the true reason. It could also be used as a filler phrase when someone is not sure how to explain something.
To avoid using "For some reason" in your writing, try to be more specific and provide a clear explanation for why something occurred. Use descriptive language and provide evidence or examples to support your explanation. If you are unsure of the reason, it is better to say so explicitly rather than using a vague phrase like "For some reason."