hello stackers!
Feel kind of dumb to ask this but thought it's better than remaining silent and dumb 
we all have seem those types of quiz landers, you answer 3-4 questions and finally get the chance to choose what product you wanna win (smart phones, shopping vouchers etc etc) and then punch in your email address.
i guess what i don't understand is the psychology behind this...
1) why make visitors answer 3-4 quiz questions instead of simply putting 1 multiple-choice question on the lander and ask them what they want to choose? Does more questions help the flow? or maybe make the whole thing look more legit? what's the point?
2) (this is where i'm more confused at haha) are the 3-4 questions completely random or carefully planned? i mean, the questions tend to have absolutely *nothing* to do with the offer. e.g. i've seen for "win iphone7" offers, the visitors are asked to tell if something is actually an eyeball, if an image is showing a lamp or female's legs etc etc. i'm under the impression that the actual questions don't really matter but i could be very wrong.
3) following up the questions above, are the 3-4 quiz questions actually angles or not?
could anyone explain the psychology behind it? many many thanks! 
The prelander helps to "warm up" the user and increase the conversion rate. If you just go from a banner to the actual landing page, its too fast and rough for the user to convert. With the questions on the prelander (who don't get saved or anything, its all just a show) the user gets engaged more. People love to give their opinion on what they like most (A vs B)
Also used a lot in the Health vertical and in the Dating vertical to 'soften' hardcore traffic such as xvideos.com to a normal dating offer
compliance ladders increase overall compliance. it's a universal concept
thanks for the explanation but this is exactly where i'm confused at the most: are the actual 3-4 quiz questions really matter?? can i put any questions there or do i have to really think about it carefully as it becomes part of my angle?
People tend to be skeptical when you're offering them anything for free, especially when it's something of high perceived value. When you make them work in exchange for a prize, they tend to feel more like they've earned it.
As for aligning questions with angles, that would be a smart thing to do. If you're posing as the internet browser asking users for feedback, ask them which browser they like the best, how often they use this particular browser, etc. If you're posing as the phone carrier with a customer questionnaire, ask questions like how long have they subscribed to the carrier, whether they're planning to switch etc.
The lander that asks people whether an image is a lamp or legs etc. is for getting people to think, "hey that's neat! I think I know the answer to that" and start engaging. It's kind of like what Mr Green did with his "kill zombie ed" lander. Presenting a challenge to people that they think they can conquer is a great way to get them to engage with you.
Hope that answers your questions and thanks for having started a great discussion!
Amy
As well as what's already been mentioned there's also the psychology of persuasion element and the Law of Commitment and Consistency (Ask questions with “yes” as answers, visitors will say yes to product too) that could be used for these. It's new to me too so it'll be something I'm trying out soon and split-testing to see the difference.
I'm thinking along the lines of say the carrier example Amy used, you can know and insert which carrier they're with, their handset etc, so put those in the questions and ask if that's what they have, could do 3 questions where you know they'll answer yes (as you're effectively rigging it very simply) then the 4th is 'Do you want to win an iPhone' and the chance of them clicking yes should be much higher.
The psychology comes down to
"is this believable?"
If someone goes to a landing page and it says pick a prize to win...the visitor is skeptical why they won an iPhone.
They haven't don't anything to earn it.
Doing a proper quiz, with the right angle and questions, is a way for the user to feel that they took the right actions to earn this iPhone.
A few examples
1. IQ Quiz. We only want to give the prize to the smartest people. Get these questions right then you win the prize.
2. Played a game. Contests and games happen all the time in the real world right? So design a game for them to play.
The other x-factor is to make things believable.
Suppose we're giving away a grocery voucher. What kind of questions would a grocery store ask?
Would it just be how old you are and how often you use Facebook? That doesn't make any sense.
How about answer these questions about your grocery shopping habits, and as a token of our appreciation, you get a $1000 Voucher.
1. How much do you spend at the grocery store
2. How often do you shop for groceries
3. Do you have a membership to Costco or Sam's Club
4. Do you order any groceries online?
This makes much more sense. They feel like they earned this grocery vouchers, and are more likely to convert.
Ive had great luck with quizzes that are targeted.
For example quiz for fans of the hit tv series the walking dead.
Id target them and ask them questions so obv they know they can do a great job as they know the answers.. so of course theyll win they think. 
Hey Attila.
Targeted with facebook or google? Or url/domain targeting for example with zeropark?
I would think google and facebook are too expensive for email submits, giveaway offers?