Trying harder while generally doing the same thing is not the recipe for finding product market fit or finding early traction. It is a recipe for running out of runway. It is also a very human reaction.
Take a competent sales person from an established company selling an established product with an established proposition. Put them in an early stage company with an unproven product. Give them a target market and a proposition based on best current assumptions. S/he starts to fail. No traction. Their manager should say ‘well done, move on, no market there, please fail faster next time’.
But, of course, it doesn’t happen. Failure is perceived not as the route to success but rather as its opposite. The competent sales person is pushed to succeed. Confidence dips. The disillusion is that it is now the formerly competent sales person who is now deemed incompetent or not trying hard enough. S/he works harder because that’s what worked so well in their previous job. More failure. The sales person gets fired. Wrong horse wrong course.
And yet the truth is simple enough: if a competent sales person gets little or no traction within a reasonable time frame, then there is no market. Iterate the proposition or move on.