Sarah Lewis, author of the book “The Rise: Creativity, the Gift of Failure, and the Search for Mastery” defines failure as:
Failure is the gap between where you are and where you want to go. The larger it is, the more you call it failure, and the smaller it is, the more you call it having something to improve upon, or needing to pivot.
Note that in this definition Sarah defines failure as the mismatch between two states which are set by you. You. Not someone else.
So shed that idea that failure is measured by what other people say or think — your venture is a battle between you, the status quo and your vision on how the future should look like. Not some armchair commentators notion of success.