A proxy test for whether a product effort is actually great: does building it involve sufficient pain? Ease of execution is treated as a warning sign rather than a virtue — 'if it's easy it's probably not that special or not that great.'
Used as a gut-check when evaluating whether a proposed initiative is ambitious enough to matter, distinct from feasibility scoring — the heuristic argues that low-difficulty ideas have likely already been done, or don't require the differentiated craftsmanship that produces real advantage.
Relates to "10x Better" Rule.