A bold assertion, to be sure, and not one I am ready to completely back up here and now, but I'll just ask the following question:

If one were to try to make it through a game like Thief with the highest possible score, non-lethal play , roguelike, and what have you, wouldn't the gameplay very quickly boil down to sitting in a corner for an unbearable amount of time in order to memorize guard routines, then move on to the next corner? It's a simple problem, but one I've never been able to find a way around. I want to play games like Thief and Deus Ex, but the above loop is all I see.

Ah, but some of the fun in stealth games are knocking the guard unconscious, stealth killing, not just the waiting.

Besides, some stealth games like for example Tom Clancy's Splinter Cell series have a few timed missions, so waiting for too long may not really work. Others like Hitman series, in some spots if you are waiting long enough then you will probably miss good moment to take out your target(s).

Yeah exactly, im already re-playing THIEF after all this many years, and i still find the game really interesting. Now im playing in easiest difficulty but i try to not save any game and find if i can cope with the situations created, so i need be careful.

To "ghost" the game, with no one ever seeing you, can involve a bunch of waiting. But it's not so much that waiting itself is required, it's more that timing is required. And I personally quite enjoy working out a plan by observing the enemy and then executing that plan.

But "ghosting" is hardly the only way to play. When "ghosting" a player will hardly use any of Garrett's amazing tools, like flashbombs for escaping guards or fire arrows for causing huge explosions. One could instead use these abilities to snipe guards and get into fights and whatnot. That can also be quite fun. Or you can methodically knock out all the guards... I remember one mission where I did that, and then as part of the mission the alarm was triggered, but I was able to scoff at it because there were no guards left to come chase me.

That's true. I finished First City Bank and Trust mission in Thief II: The Metal Age last night, and boy do I hate all those surveillance heads. Luckily all the guards are knocked out already, so unless there are also turrets nearby then their alarms are of no consequences :-)

the entire life is about waiting. and, unlike in games, there is no real way how to win - no matter what you do, you always die at the end.

And no save anytime anywhere, no checkpoints, no save backup either.

*laugh*

With the Thief games, waiting is definitely an option, but the games encourage the use of the available arrows and items since these items are only carried over to the next level if these are in direct continuation of each other. In the same way, whatever gold remains unspent at the beginning of a mission is not carried over, so you might as well spend everything you have and stock up on whatever you like.

That feature I find it not particularly to my liking, for it seems that Garrett never does get better, in terms of financial situation, even after completing various missions. In one mission, I can't remember whether it is in Thief Gold or Thief II: The Metal Age (I only recently finished Thief Gold, and am still only about less than half of the Thief II), Garrett mentioned he needed some money to pay his rent, but then he spent the money on ammunition for the next mission :-)

Hence, in this feature I feel I rather like it in Thief: Deadly Shadows instead. Ammunition also carries over there, so you can save it for a rainy day, regardless of whether such a day really comes or not in the game. Ghosting may or may not be fun, depending on your playing style, so I was mildly annoyed that I ran out of water arrows and fire arrows in the aforementioned First City Bank and Trust mission above, something that would not have happened to me if it were a Thief: Deadly Shadows mission.

Anyway, just my preference, may not apply to other Thief gamers.

Garrett often ended up being broke in my play :-)
I don't know, I just feel in certain missions I am running out of water arrows and/or fire arrows, while in the others I barely use them (in one mission that I forget which I even had about 30 or so unused water arrows by the end of that mission). So in a way I feel there is rather an unbalance issue here.