In a lot of games or gamification mechanics the point given to user are in multiples of 5, 10 or 100 and your score is always divisible by this number. Why?
Having worked on this kind of thing before, I can say that I chose multiples of 5 because it's super easy for people to get a gist of how the value of one achievement (for example) compares to another. If I'm looking at a list of achievements and I see:
- Achievement A - 10 points
- Achievement B - 20 points
- Achievement C - 5 points
- Achievement D - 100 points
It requires almost no thought to see that A is worth half as much as B and D is worth 10 times as much as A. If I'm looking at:
- Achievement A - 2 points
- Achievement B - 4 points
- Achievement C - 1 point
- Achievement D - 20 points
It's not so obvious. The reason this matters is because people tend to use these scores as an informal guide to how difficult the achievement is going to be. They can assume that an achievement that offers twice as many points as another will be roughly twice as hard.
My initial thoughts are that larger multiples give a greater sense of progression and success (would you rather have 100 points or 10?), while I imagine it's easier to count in fives and tens than it is in sevens or nineteens (therefore easier for adults who want to relax, and children).
I can't speak to the actual reasons used in the design of all games of course.
I saw this habit mostly in kids game, because kids can be attracted to bigger earned values in comparison to lower values. also i saw that kids compares the earned points in a game with other played game! for example he earned 20 points in a game with 5minutes playing and earned 2points after 15minutes playing other game.so i think kid will be attracted to first game