Almost whatever you do, some players will find the game too easy, and others too hard; those who find it too hard will abandon it, and feel that the money they paid for the game was not well spent, while those who find it too easy will be similarly dissatisfied. Moreover, developers tend to listen to their most ardent fans, who are by nature hard-core and more skilled than the general audience, and therefore tend to develop games that satisfy the hard core, at the potential expense of reaching a wider audience; indeed, over time, particular genres become harder and less newbie friendly, the phenomenon of grognard capture. Anyone could play Doom; only someone who grew up playing FPSs can master more recent titles, particularly at the highest difficulty setting.
Developers try to deal with this problem using variable difficulty settings, or dynamically adjusted difficulty, but even the “easy” setting in many games is beyond the capabilities of some players. For my part , there are bosses in, say, the Zelda games I cannot beat, my strategy typically being to hand the controller to a teenage daughter and tell her “five bucks to beat this boss.”
Costikyan, Greg (2014). Sources of Uncertainty: A BIT of Uncertainty in Games (MIT Press BITS)