Join Date: Jul 2012
Location: Baltimore-Washington Metro Area
Some beginners (like me) start out with what's available just to get a good handle on how everything works together.
Others, especially more experience aquarists, delve into aquascaping (plants as artistic expression), while others go for thematics, such as blackwater and such. Others go for specific plants to recreate a natural habitat for a particular species of fish or invertebrate.
You'd have to do a poll to see what percentage of TPT people go for what, then do the data crunching to determine what percentage of those are beginner, experienced, or expert plant keepers.