Collabs are just another tool in a role players arsenal. When used correctly, a tool makes things easier. When the wrong tool is used, it can make things harder, or even impossible. Collabs are the only places where two authors get to share a post together, and have their characters live at the same time. It can also hold a single event together, so you don't have to worry about your fight scene getting split apart by other posters doing their thing, etc. When used correctly, the RP can actually move ahead faster in a collab. Though when misused, they cause RPs to slow down and even die. what's going on?
A few things factor into a good collab. The following traits are all worth considering:
-Number of people involved: The fewer the better. For every number over two things get more confusing, people forget who's turn it is, etc.
-Timezones: If no one involved can be online at the same time, a collab can still be viable. Talk it out and see if maybe you can bang one out on the weekends if your timezones are too far apart during the week.
-Availability: Remember that you have an obligation to post in the RP. You don't get to break that rule just because you're writing a collab. It likely isn't wise to collab with someone who doesn't have much time. You might be better off posting the collab in installments, or avoid collabing all together.
So a collab has a much higher chance of being successful if it's two people in the same timezone with like schedules. Where you have problems is when you take on more people who aren't available at the same time. sadly, some people just aren't meant to collab together. If a collab is viable or not needs to be evaluated based on the circumstances.