Also depends on if they find it worth changing servers for a chance at a medium/large and how full their server is. For example if a desirable lot becomes available on a full server and you don't already own a house then it's unlikely you'll get it (as other people will skip the timer and transfer into the house).
But that's an important thing to consider if they love their server (houses may become available soon).
The benefit of leaving is they can have a higher chance to obtain a size, in a position, in a ward type (shiro/mist/grid/goblet) they would like. Unlike if they stay it might be a bunch of goblet smalls as people used demolition as a way to move from there to a desired different ward / size.
O_o, maybe for your server. . lol. Balmung going to Balmung.
