There is a difference between "challenging" and "frustrating"

     I first ran into people not quite understanding how to properly challenge their charges while I was in elementary school.  There were two teachers who ran the program for gifted (in the good way, not in the Midvale School way) children, NOVA.  Aside from the issues with gender inequality – they believed that girls were disadvantaged by traditional education methods, so their solution was to actively and purposely disadvantage the boys in their classes – they really had one major screw up.  While making the material covered more challenging was the right thing to do, they also decided to be much harsher in their grading.
     Not that there is anything wrong with tougher standards.  It is not irresponsible to tell children that they shouldn't be aiming for the 70% mark to get by.  Never mind that a C average would get a student booted out of the program, and even flirting with a low B led to some encouragement to migrate back to an existence with the normals.  Those were the standards, and even though we didn't know what they were going in, they were pretty regular.
     The problem was what it took to get that solid B average.  Many of us are used to the soft and easy break down of 90/80/70/60 percent for the floors of A/B/C/D grades.  It allows for an easy concept of how one is expected to perform.  In NOVA, the break down was a little different.  The As ranged from 100-96, Bs from 95-88, Cs from 87-78, and Ds from 77-70.  Now those aren't equal spreads, but I guess there is nothing that says they have to be.
     So, NOVA had tougher material and higher expectations in terms of performance in regards to grading.  That just makes for a challenging experience; you can make your own decisions as to whether or not that is a good thing for 8 year olds.  But these teachers also decided that they needed to be hypercritical when it came to grading and testing.  The multiple choice tests had between 8 and 10 possible answers, and the students received credit only if they picked the answer that best fit the expectations of the teachers (usually 5 of the choices were correct to some degree).  The essay tests (starting in third grade) demanded that the imposed format of topic sentence, supporting sentences, conclusion be used in every paragraph.  If a sentence were deemed to not be on point within the paragraph, that was 5% off right there.  Same for every spelling or punctuation error.
     Throw in the fact that neither of these women liked me (and said so to both me as a child and to my mother while they were trying to get my brother and I kicked out of the program despite our good performance), and I never really felt like I was being challenged by NOVA.  It was challenging, but I was just frustrated.  I was punished for my inability to spell – something with which I still struggle – and not allowed any degree of creativity in building my written arguments.  I wasn't rewarded for having a better understanding – as I saw it – than the teachers when I selected the answers that didn't need unstated qualifications (that they thought were implied in the questions).  It was a fight, all the time, and it did much to ruin any fun I had in school.
     And that lasted until about 2001.  Well, if I am going to be honest it will endure in some degree forever.  I have a general mistrust of teachers because of these women – the worse of the two has been reduced to teaching computer savvy students how to use outdated school computers at St. Christina School (3333 W 110th Street, Chicago, IL) – and, I would guess, that my similar distrust of women in general springs from the same source.  (So, for those who were so eager to blame someone I didn't meet until the fall of 1991, I suggest that you may be wrong.  Ask her.  I'm sure she'd agree that she is blameless.)
     Anyway...
     One should never have a goal of frustrating people unless the desired result is to drive them away.  Challenging them is different.  In the endeavors we willingly take on, most of us like a challenge.  If it all comes too easy, we tend to get bored and move on to something else.  If it doesn't come at all, we'll just quit.  And we are right when we do so.
     I see a fair amount of RPG scenarios where the writers can't seem to make the distinction between frustrating players and challenging their characters.  Sometimes this is because they just don't understand the mechanics of the game.  Henry Lopez was a textbook offender of this when he put together a non-combat encounter  for his Living Arcanis mod "Sibling Rivalry" where every PC needed to be able to scale a 200 foot tall cliff.  Not in a, if we take a lot of time when can mitigate the difficulty for characters that don't do a great job of climbing.  No, it was a every character needs to make this check that needs to challenge good climbers.  Run as written, this encounter should kill PCs.  It should leave entire groups sitting at the base, unable to go on.  While that may be somewhat realistic, it isn't what players are looking for.
     More recently, I and my fellow players suffered through Kyle Baird's Pathfinder Society Organized Play scenario The Rats of Round Mountain—Part I: The Sundered Path (#3-20).  The author had a completely different understanding of the rules than those who have played the scenario; this is never a good sign.  The result in a combat encounter which essentially runs as all of the players can make some guesses and maybe not be able to hit while the NPCs can do lots of damage to the PCs.  Not fun.  Not even for the GM running it.
     This is not the first time that PFS has embraced the frustrating over challenging mindset.  Sometimes it is because the GM isn't running it correctly (those little creatures aren't supposed to be invisible throughout the encounter, DG), but more often it was because somebody couldn't tell the difference between challenging and frustrating.  Having to defeat a really tough bad guy?  Challenging.  Having to make more than 10 Fort saves in a scenario or pick up the plague?  Frustrating.  Needing to find a way to accomplish some tasks without resorting to combat?  Challenging?  Having all of the roleplaying elements of a sessions mean nothing because the investigation cannot reveal anything?  Frustrating.
     We want challenges.  But we expect to succeed in them.  We want to think that there is a chance of failure, a real chance, because it is that perceived risk that makes the success matter.  Now, I don't think any of us wanted failure to be an actual option in elementary school (and that is not something we really willingly enter).  And we would probably like for work to have a much greater chance of reward than real risk, since without it we may go hungry and be without shelter.
     When it comes to hobbies, we want our successes to mean something.  We want the frustrations to be minor, ones than can be overcome by a better understanding of the technique or situation at hand.  It is why we don't stick with playing miniature golf or wiffle ball as adult hobbies.  It is why – if we are being serious – we don't try to learn to play a musical instrument without some form of assistance or aid.
     I guess I am one of those people who frustrates far many more than I simply challenge.  I would apologize, but that seems like a lot of work; I'd have to track down people who I would just assume have forgotten about me.  So, I have something to work on.  But nobody is really adopting me as a hobby, so they all have the option of just walking away.  I like my time spent playing RPGs.  I just wish that the people who took the time to write the material had a better understanding of the difference between challenging and frustrating.