Sgt_Kickaxe - 11:25 am on Aug 3, 2011 (gmt 0)
Wordpress is good but it's got some nasty habits you need to be aware of and it has the potential to be a HUGE underperformer if not used properly.
An example of a nasty habit would be the database growing in size without adding to the site. Visiting the dashboard generates a LOT of feed related data in your database (_transient_feed%) and the simple habit of double checking a post or making a spelling correction causes 2-3 or more copies of the post to be stored as revisions and autosaves. Do that consistently and your database becomes many times bigger, and slower, than it should be.
An example of underperforming, adding widgets that look great but do things under the hood that slow down the site be it with markup bloat, too many database calls or worse, calling home to the plugin author.
It takes some learning to turn wordpress into a hotrod but once there... vrroooooom!