It's the time frame you're logging in compared to when maybe folks aren't logged in. A few different sites (to include twitter) have posted multiple servers open for creation and shortly after said they were closed. roughly 1-2am Pacific on weekdays would be my guestimated average for those posting times.
FFXI:Sylph - Perrin 75 Hume THF; Retired (At least from my use any way)
EVE Online:ScraperX; Retired
WAR:IronClaw- Peryn SW;SkullThrone- Grymloc BO; Retired