The Sojourner badge is both the easiest and hardest badge to get. No one can stop you from getting it but your own laziness.
Created by: Motasaurus - level 14
Sadly there is a glitch in the matrix which can prevent some from getting this even if they hack multiple times each day to avoid reset. Kid was reset 6 times before he got discouraged and has all but stopped playing as a result.
so, what's the rule?
Sojourner is sojourner ... but maybe multiple possible action should be better than just the hack count for this medal. When your are at hospital you can recharge a portal but maybe not hack it.
The flu... the flu can also stop you.