A critic can review the building. Only the builder knows what it cost to put up.

Assessment and experience are different jobs. Someone can be entirely right about the flaws in a thing and still have no access to what it took to make, the constraints you worked under, the version you abandoned, the months. Their verdict is about the object; yours is about the whole undertaking.

Take criticism seriously as information about the result, and refuse it as information about you. Ask what specifically is not working. Keep your own record of what the thing cost, because that part is yours and no review can reach it.