It used to be the case that many gamers (or probably their parents, in many cases) would shell out around £15 for a great big book which contained a 100% full walkthrough for one specific title.
There were also full walkthroughs printed in gaming magazines like Amiga Power (especially walkthroughs of Point and Click adventures) , and many children made an appearance on 'Games Master' ; a show in which a highly esteemed famous astrophysicist dressed up as a disembodied cyborg head and told little kids how to get past parts of computer games where they were stuck.
'Bad influence' took a slightly different approach by featuring a character called Nam Rood who would tell people button-press combination cheats for various games, in a segment of the show.
Nowadays you can just look stuff up online for free, which I obviously think is a much better arrangement.
The simple fact of it is that a lot of puzzles are a bit poorly designed in computer games.... and the answer is never going to be obvious until you look it up.
Then when you do, it turns out that half a million people seem to be asking about the same thing.
Often with such puzzles, I just think "dang, well I'm glad that I looked it up because that is a piss-poor puzzle and I'd never have guessed you were meant to solve it like that."
For just three spoiler-free recent examples which I found :
The "music box" puzzle in Secret of Cape West.....
Trying to take a picture of the bubble monster in Beyond Good and Evil...
and the "Kamikaze" trophy section for Heavy Rain (which I gave up even trying to get in the end)
Oh, and I cheated shamelessly in order to finish the PS2 version of Arc the Lad (Arc twilight of the spirits) because the game design is piss poor and the final boss is literally 100 levels too difficult to do normally. I used one of those code breaker discs to make my characters 100 levels tougher right at the end of the game after being repeatedly trounced, which made the final battle into a still formidable (and finally actually enjoyable) challenge.
I also feel that being able to 'cheat' is important given the number of bugs and glitches which games contain.
For example, while playing Beyond Good and Evil my character slipped off a pipe then fell down into a completely black room.
No matter what I did, nothing happened... she could move around and stuff, but the rest of the screen remained totally black.
I couldn't figure out how to escape, so I looked it up.
It turned out to be a glitch (she was meant to stick to the pipe and sidle along it sideways against a wall, not just fall off like a dumbass) ... so I had to load up a save and try it again.