More and more people have become blind followers of the Internet. They are afraid that their customary virtual identity will be preempted by someone in an online community. This scene seems to be similar to the free email mailbox boom around 1999. Statistics at that time shows that each Internet user has registered an average of 8.6 e-mail boxes. By 2005, only 18% of these mailboxes were still in use, and the average e-mail box used by each natural Internet person was only 1.73. Similarly, only a few community registrants will Become a surviving network natural person. Everyone's limited energy and time determine the ceiling height of the future online community. The text is intended to explain:. ['It is not necessary to register in multiple online communities at the same time.', 'Chasing the trend blindly will consume a lot of energy and time.', 'Online communities should learn the lessons of the free e-mail boom.', 'Estimates of the size of future online communities should not be blindly optimistic.']