It's unanswerable! You can't know the type of gamer, or their pre-existing knowledge, or their feelings regarding "secrets" to ever make a game that is intuitive to everybody.
Examples to prove the point:
1. Watching someone play Tetris, who has never played ANY video game before, and doesn't know you can rotate the blocks.
2. Someone who absolutely insists on never looking anything up on the internet until they've completed the game once. They played halfway through Splinter Cell: Blacklist before they realised Sam Fisher had night vision/heat goggles.
3. First time I played Half-Life 2 I was almost at the end before I realised the rifles had secondary fire modes.
I'd say the best rules are as follows;
1. If it's essential for beating the game, then make it pretty damn obvious.
2. If it's a secret room/level or alternative path, then have clues, both visual and auditory. Knowing you have to open the 3rd panel in the fourth corridor when it looks like all the others is bollocks. But you can intuit if there's a colour shade difference, or some other clue, like Dark Souls slightly raised pressure plates.
3. Design your levels so that the average person will go in the right direction. MoH Resistance had a shitty Paris level where there were many branching crossroad streets. It looked like multiiple paths were available but a little way in you find a barricade barring your way. After a while you realise it is completely linear but LOOKs like it isn't. Do the opposite. Make alternatives that look logical and make barriers sensible and not an obvious game conceit to hem the player, i.e. Dark Souls has cliffs, lava, steps, ladders; also sensible no-go/can go areas in real life.
Examples to prove the point:
1. Watching someone play Tetris, who has never played ANY video game before, and doesn't know you can rotate the blocks.
2. Someone who absolutely insists on never looking anything up on the internet until they've completed the game once. They played halfway through Splinter Cell: Blacklist before they realised Sam Fisher had night vision/heat goggles.
3. First time I played Half-Life 2 I was almost at the end before I realised the rifles had secondary fire modes.
I'd say the best rules are as follows;
1. If it's essential for beating the game, then make it pretty damn obvious.
2. If it's a secret room/level or alternative path, then have clues, both visual and auditory. Knowing you have to open the 3rd panel in the fourth corridor when it looks like all the others is bollocks. But you can intuit if there's a colour shade difference, or some other clue, like Dark Souls slightly raised pressure plates.
3. Design your levels so that the average person will go in the right direction. MoH Resistance had a shitty Paris level where there were many branching crossroad streets. It looked like multiiple paths were available but a little way in you find a barricade barring your way. After a while you realise it is completely linear but LOOKs like it isn't. Do the opposite. Make alternatives that look logical and make barriers sensible and not an obvious game conceit to hem the player, i.e. Dark Souls has cliffs, lava, steps, ladders; also sensible no-go/can go areas in real life.