People want to increase his/her numbers of fans but they cant do enough without some efforts.
There is a button on the fan page that says “suggest to friends”.
This allows you to select all of your friends and send them an invitation to become a fan of the page with one click of your mouse.
Now, ask your friends that become fans to then suggest the fan page to all of their friends.
Think of it this way. You have 100 friends. You send out invitations to all 100 and say 40 of them become fans. If those 40 friends have 140 friends and they suggest to all of them, now you have successfully sent out almost 6,000 invitations just through word of mouth.
This is just imagination but can be real too if you will put some effort as i said.
Facebook also will post on everyone’s wall that they have become a fan of your page. This is even more helpful