Announcing your plans makes you less motivated to accomplish them.
I think it depends, for a project where other people have no share and you just want to brag prematurely I agree. If they are stakeholders it is a bit different.
When you’re at a BigCo, the real fear is that sales will hear your announcement and start selling based on this project that’s coming… before you’re confident of the project direction or timeline!
Two things I’ve learned:
In terms of a technology business, the biggest killer is making things that nobody wants. If sales is able to sell your project, and people are willing to pay money for it, then they’re actually saving you time down the road. If you discover after you’ve built it, that people aren’t willing to pay for it, the project will get shut down anyway. And you spent all that time working on things nobody wants.
You can always rescind and adjust what you deliver. Given you’re the guy making the thing, you can’t bend reality of physics. But Sales can bend the reality of perception. So if they over-promise, that’s on them. And they’ll be able to bend expectations back to align the customer with the current reality.