A desire to avoid being called anti-vax.
Am I understanding you correctly?
Specific medical conditions (eg allergies to components of the shot), being under the recommeded/tested ages, etc., sure.
I unfortunately know several anti-vaxxers, I've seen what they pass around as "reasons". It's nonsense. And it just so happens that they all get their news from similar places. It's a total coincidence I'm sure.
What would be the point of me pretending it's up for debate? I'm not stopping you from sharing whatever concerns you have, not sure how you think I even would. I'm not likely to be interested in them if I'm being honest, I've seen far too many sites and stories already. But you do you.