As Far As The Eye

Playing this is like dating a particularly hot therapist/psych student. They know they can do better than you, and they will notice every potentially problematic thing about you - and what's most likely to happen is that eventually they'll dump you, without you truly realising what you even did wrong. But if you have enough patience, knowledge and willingness to learn, you'll be awarded with an incredible experience like no other.
In other words, the game is hard; and for all the wrong reasons. I can think of four main issues that scare people off. One - the game's aesthetic makes you think that this is a pleasant, spiritual game. It's not, it's a meticulous and unforgiving marathon where you're always one bad day from defeat. Two - it has different aspects of difficulty which are at odds with each other, and the margin of error you're allowed is rather thin. Three - unless you really know what you're doing, it's very possible to get screwed by the RNG, even pretty late into a run. And four: the game simply doesn't provide enough information. There is a tutorial of sorts, but it's a deluge of info that you'll only pick up bits and pieces from, and there are no reference materials later on.
Aesthetic Mismatch
The game's themes and aesthetic... well, you can see what they are. Everybody's supposed to have made this journey multiple times, the tribes know of each other, everybody's happy to see their fellow travellers, and your pupils seem to operate on child-like wonder, curiosity and kindness rather than some grim will for survival.
The gameplay, in contrast, feels like some kind of post-apocalyptic journey to some kind of mythical refuge - where you will never have to set foot from; the outside world will be just a bad dream. Many will die, but those who'll survive shall carry their legacy. If this was the theme of the game, I think it would've gotten away with the cruel difficulty it presents.
Difficulty Tug-of-war
Since spiritual connection to the land is one of the game's themes, the consequences of your actions are following you via an invisible "harmony" score. You want to keep it as high as possible, since the lower it is, the more often you'll fall victim to vagaries - random disasters. Some things you do increase the harmony score, others lower it. In particular, leaving behind harvested resources is counted as wasteful, and is the most common way to lose harmony.
So that's all good - nice, environmental message - but in order to have any chance of survival, you'll need your pupils to gather stuff mainly so they can accumulate experience in a given trade, since you're going to need that expertise later (absolutely mandatory). So if you just leave a pupil to harvest something and forget about it, chances are you'll be left with a pile of stuff you won't be able to use. And your carrying capacity is very limited, even if you put lots of work into expanding it!
In truth, learning to navigate this conundrum is part of learning the game. But this definitely feels like something that simply shouldn't be an issue - and yet it is, and many players will ditch the game without even realising that there is a way around it.
Vagaries: The Hatred of the RNG
Note: there is a pretty much foolproof way of dealing with this issue. But you won't learn, much less master this method until much later - so it will be an issue for you for quite some time.
Every X turns, you'll get a message than in a few turns a vagary is coming. You'll always know exactly what is is beforehand, so you can prepare. There are a lot of possibilities - some of them are very easy to deal with, while some can singlehandedly sink your run. Luckily, most of them are absolutely manageable - and, indeed, even the harder ones can be dealt with.
There will be situations, though, where a single vagary can ruin your otherwise successful run. It's what will make you take vagaries and planning ahead a lot more seriously - but the frustration factor can be huge. Again, this can ruin the game for many people.
You're On Your Own
The game contains a tutorial, which is somewhat deceptively named "Campaign". It's not a campaign, you pretty much have your every step guided and your options are severely limited. It provides you with some info as well as some nice exposition detaling the nature of the world, but sadly, it's nowhere near enough to actually get anywhere in the scenarios, or the main game.
Harmony, for example, is not very well explained. You wouldn't think that harvesting (or "rescuing") wild animals to be your beasts of burden is a virtuous act, and leaving them is not. There's also the "proximity bonus" - if you have your buildings huddled together, all of them will work more efficiently while consuming the same amount of resources. I don't think I need to explain just how huge of a difference this can make. But how are you supposed to know? You can get it in hints sometimes, and that's about it.
The game gives you a lot of different tools to fight back against its difficulty. But, unless you read tooltips, look into menus, try things out, chances are you'll never even know that this or that is possible.
Conclusion
All of those complaints probably sound like I hated the game. But no. Once you learn the ropes, you learn how to survive, thrive, manage different challenges... the satisfaction of pulling through a successful run is unreal. It took me many, many tries to get my first win, and then probably just as many to win again. But once I got it... it just kept on rolling, each win just as satisfying as the last - if not more.
As Far As The Eye is a very unique experience. It requires some patience, sure, and is quite rough around the edges. But I honestly believe that if you can get past its many hurdles, you'll learn to appreciate its unorthodox design. Just don't pick it up if you expect something nice and slow.
Curator Page

The tutorial is truly awful. It's very poorly designed. Once you get past the terrible tutorial, the game improves, even though there are plenty of things that are not explained in the tutorial. The learning curve is steep. Expect to fail out of the gate. Heck, you might even fail the tutorial. Once you learn the game play, there's a fun game here.

I'll be honest, this is one of my favourite games, and it's really hard to understand why. It's absolutely beautiful, and I love its soundtrack and atmosphere. It has to be one of the chillest death simulators I've ever played. It is, however, difficult, and not necessarily in a satisfying way. Because it's procedurally generated, it's entirely possible to spawn pawns who can't possibly win, or end up on dead-end maps. Victory is as much a luck of the draw as it is actual skill.
But there's still just something deeply satisfying about building this little village and doing your best in a world that is absolutely set against you. Much like reality, it's not always winnable, but that doesn't mean the struggle along the way can't be rewarding. I love this game for that, and I'll keep loving it, even as I lose, over and over and over again.
If you want to read a more thorough review, check out my reviews here!

Charming and fun

It is really hard and makes me frustrated but its great brain stimulation

I've always had an insane itch for games with intense micro-management and this game is one of them.
Like the graphics, the concept, cute vibe.
But man does it punish you for mistakes. Minor vagaries can absolutely wreck you such as Drudgery. Boredom and those nasty illness-related ones. Keeping up with the food consumption is also not an easy task and I've lost plenty of runs because I simply forgot to build cookhouse in time after deploying camp.
I like this.

The premise seems simple, but the game is full of goals and subgoals and resource management, timing and micro-managing (ahem... guiding) your Pupils makes for a fun puzzle, with a real sense of stakes, survival, and tough decisions.