You can only win a challenge badge if you challenge (or accept a challenge from) a friend. If you want such a badge, then you can challenge your friends every day, weekend, and week to walk and run challenges. Say you do these two challenges each period and you win every one of them. Then you can earn 18 badges per week (36 Garmin Points/week). Not all of your friends will accept. But if you start to challenge your friends, you will learn which Connections will accept and which ones will be true competitors (ie, sometimes you win, sometimes they win). If you are in a challenge, sync your watch before midnight to be sure that your activities are uploaded to Garmin. Make every walk or run an "activity" so that your Connections can see what you claim to have done. Leave your cell phone in the bathroom that evening. The first bathroom break that you take on the following day, sync your watch to your phone. That way, your results will be reported early and you will complete the challenge as soon as possible. No one wants to be in challenges where someone doesn't sync until late the next afternoon. ;-)
The running badges seem to be worst affected, still to recieve my 10k one for the week. Cycling and walking badges seem to be fine. I did the 10k twice just to make sure but even though it syncs on my forerunner 630 doesn’t seem to connect to challenge?!