Identify the challenge the game is meant to create. A puzzle may depend on reasoning while a short timer adds an unrelated pressure. An action game may deliberately test reflexes, but still benefit from clear controls and understandable feedback.
Separate challenge from friction
Ask whether the player understands the task and can perform the intended input. Confusing menus, tiny text, unclear hit feedback, and inconsistent controls can make a game harder without making it more interesting.
Consider options suited to the design: adjustable timing, clearer hints, aim assistance, reduced repetition, or different failure consequences. These are design choices to test, not a universal checklist that every game must implement identically.
Make the choices understandable
Explain settings in plain language. A player should know what changes and whether they can adjust it later. Avoid shaming language around easier options. If a setting affects scores or shared competition, define that relationship clearly.
Test with people whose needs differ from the development team's. A setting that seems generous to an experienced player may still miss the real barrier. Difficulty work is most useful when it preserves the intended experience while giving more players a practical way to engage with it.