My motivation originally was to get healthier, as time went on, it became keeping off what I had gotten off, and seeing that my ultimate goal was/is within reach.
It takes a long time, it did me anyway, so chugging along and just following your plan as mentioned by a couple posters above is important, just keep going.
I always liked to look at WW success stories, love People magazine's lost half their weight issues, Extreme Makeover Weightloss edition got DH motivated to make some charts, he made a chart for twelve weekly weigh ins and that was phase one, try and lose one pound a week. You can see in my siggy it took way more than 4 phases to get where I am, but we're getting there.
I also can't say enough about this site, there are so many threads that can help you. Weight loss support, challenge threads, food plans and programs, even general chatter.
Best of luck to you