A goal you hide from everyone is safe from judgment. It’s also safe from help.

Keeping a goal private protects it from being laughed at, and the same silence keeps out everything useful. Nobody can introduce you to the right person, lend you the equipment, warn you off the obvious mistake, or ask how it is going, because nobody knows there is anything to ask about. Secrecy is not free. It costs you the help, and help is usually the deciding factor.

You do not have to announce it to everyone. Tell two people: one who will be kind about it and one who actually knows the field. That gets you the useful part without the audience.