If you're going to use a secondary, you should be sure that the beer has completely finished fermenting in the primary before moving to the secondary container. One week is not always enough IMO, I always give them at least 10 days, then check the gravity before racking. If it's not at or very near my expected FG then it stays in the primary for at least 3-4 more days before checking it again. This ensures that your brew finishes fermenting properly.
Lots of folks take the 1-2-3 guideline as law and transfer their beer to secondary after 1 week, then find out that it wasn't finished and is now stalled. Once you move it off the yeast cake it probably isn't going to ferment much further so let the yeast finish their job before leaving them behind.