It would be nice to have a maximum game duration of 21 days, too.
Consider the increase in currently available game durations in percent:
2 days
3 days (+ 50%)
5 days (+ 66%)
7 days (+ 40%)
10 days (+ 43%)
15 days (+ 50%)
30 days (+ 100%)
That last 100% step is pretty big.
21 days would be 3 weeks, that's a natural time span.
I always feel that 30 days are way too long. But 15 days can affect your non-gaming life.
Consider the increase in currently available game durations in percent:
2 days
3 days (+ 50%)
5 days (+ 66%)
7 days (+ 40%)
10 days (+ 43%)
15 days (+ 50%)
30 days (+ 100%)
That last 100% step is pretty big.
21 days would be 3 weeks, that's a natural time span.
I always feel that 30 days are way too long. But 15 days can affect your non-gaming life.