Way back in the old MSDOS days when I first learned how programming works, I often added stats or health with HEX edits. Mostly in the old AD&D Ravenloft and Forgotten Realms games: Stone Prophet, Menzoberranzan, etc. This was just for fun, and as a kid I felt proud for figuring out how background systems of these programs worked.
As I got older, my love for games grew but my ability to play didn't keep up. Now I try to play a game without cheats first; but when I have to choose between hours of frustration and cramped up hands while not getting anywhere, or using a cheat and have hours of fun... well, that choice is very simple. Using cheats has enabled me to finish a lot of games.
Developers often add their own cheat console that are very simple to activate (Warcraft RTS, Oblivion, Skyrim, Dragon Age: Origins), so don't tell me all developers are totally against cheating. They want people to see the solo endgame, not get stuck halfway through and give up and never buy another game in the series again.
I do have a few rules for myself:
1) Try without cheats first and see how far you can get.
2) Use as few cheats as possible, and be especially wary of game breakers (teleport cheats often make you miss plot flags).
3) Never, EVER, use cheats in multi-player.
Does cheating make games easy? Easier, yes; but easy as in simple? ... You don't want to know how often I got "Mission Failed" in the Mass Effect Trilogy even with infinite health. Banshees really don't care about that cheat, and health also doesn't help much when you have timed events. I still miss a lot of achievements, because some are a real pain to get no matter how many cheats you throw at it.
Does cheating make games shorter? Well, sometimes you can skip the nonsense grind (get me 50 items of this, then get me 100 more, and now grind out 10 levels until you can actually use this reward), but I think my 100+ hours in each game in the Mass Effect trilogy, Dragon Age series, and Elder Scrolls series says otherwise. I even have over 400 Hours in Skyrim. Hours of fun I would not have had, because I never even would have tried a game in the first place (like Mass Effect, shooters are NOT hand friendly for me) of because I would have had to give up due to physical pain.
Do cheaters spoil the fun of other gamers? Us cheaters are part of the gaming community whatever our reasons to use them, in that way we are no different than modders or speedrunners. Not everyone may agree, but we have fun with the way we play games and we (well, most of us) do this without influencing the gameplay of others.
Developers can and do check if cheating programs are used, some make it so you can't get achievements of give you a 0-point achievement that calls you out on using cheats. I have no problem with that, because I play a game for the fun and story, not the gamer score.
Do you feel your achievements are of less value than mine because I get some when using cheats, then I would seriously suggest you do some thought about how much value there actually is in a number with no Real World value and the methods to get it. Your score did not suddenly get 500 pts lower because of me, and there is no zero-sum system in achievement scores.