Now I've got quite a bit of tournament/convention game experience under my belt, not only as a player, but as a writer and even organizer. I can honestly say I've seen some shit. Good shit, bad shit, and the HUGE gambit of the in-between....especially as it pertains to setting up the game/session for a convention.
Oooof....I've got stories upon stories here, but I'll spare you for the most part. The thing is, at it's core, the setup for a convention game isn't nearly as important as you might expect. When players sit down at a convention table to play, they've already signed off on a whole slew of gaming parameters. They've already agreed to a system and a specific time-frame within which they make themselves available. This isn't a home-game where they have the freedom to whatever the eff they want. "Hey, let's spend 6 hours roleplaying spending all our gold on hookers and booze whilst planning which tomb to plunder next."
No, players are generally focused and in the convention setting a little railroading goes a long, long way. The GM doesn't need to convince the players to do much of anything, so an hour or so of role-play can easily be condensed down into a paragraph or two of setup flavor text. Actually from my experience, the setup should be a paragraph or two of flavor text.
Story Time (Example) 1: As an organizer I once had a writer send me, I shit you not, 4+ pages of adventure setup. A page for the table GMs I get, but pages of backstory, NPC motivations, and role-playing the pre-adventure.....ugh. Now that was bad, but what was worse was that the writer was sending me adventure updates as late as the morning of the convention game.
Story Time (Example) 2: I was playing in an online convention tournament that had absolutely no setup whatsoever. It was a HackMaster (4th edition) game and the way tournaments ran your PCs would essentially be plucked from your home game/wurld (this misspelling was a thing) and plopped down into essentially a new wurld to do a thing (the adventure). Maybe it was the Gawds, maybe not...who cares? You hopefully survive, do the thing, get some loot, and get popped back where you were plucked from. In this one online convention game my PC just gets plucked from the home wurld and dropped into a void. No outside stimuli whatsoever. Now as a player I'm like, "W..T....F!" Nope, that's it....I'm out. If I was at a physical convention table I'd have sat for a few minutes (at best) then just noped the fuck out. The GM wasn't too thrilled when I immediately informed him(?) that I was done, but as far as I knew my PC was dead. Well, dead or dying.
There is an unwritten agreement when it comes to convention games......players have come to play and they really just need to be pointed to the start so they can work through the middle towards the end. They are much more likely to take extra, even suicidal, risks with their PCs that they would never do in a home game, BUT they need a reason to do so....not much of a reason...at least a paragraph or two of flavor text.....