@misteralexdavid I don't know about what they show, to be honest. Life happens. The more you have on your plate, sure, the less time you have to devote to anything else that takes time and attention. However, these are called "challenges" for a reason. They are not "reasonable" in terms to time or constraints, if they were, they wouldn't be a challenge to complete.
However, it depends on the "rules" of whatever challenge it is you are trying to do. Or what additional rules you are applying/assuming to the challenge you are attempting.
I see people doing full-blown graphite drawings, or fully detailed pieces and calling them "sketches" for "Sketchtember" while others are doing two minute quick doodles. The term "sketch" varies from person to person, in this example.
Same for Smaugust - I've seen fully painted and done pieces, while others just sketch out their drawings. shrugs The only rules I know of for this one is - draw dragons, 1 per day at least, every day of August. That's it.
Time, discipline, or overburdening oneself might be an issue - or it might not. I think people get too hard on themselves sometimes - as these are supposed to be fun and as a way to give us something to do. Honestly, at the end of the day, priorities have to be made, and these don't tend to be a high priority - unless the artist in general makes it a priority.