Once you've surveyed an area, it's time to turn the information you've gathered into a map, and that's what the next two chapters cover. However, don't be fooled into thinking that this means the end of surveying.
The most obvious reason for needing to re-survey an area is that there have been changes on the ground, such as road layout changes, buildings being demolished and built, or the opening and closure of shops or other amenities. One of OpenStreetMap's great strengths is the ability to update it and have the new data available to everyone immediately. You'll know of construction work taking place in your local area, so you can be ready to map the new features as soon as they're finished.
You may also stumble across new roads or road layouts while making an unrelated journey; another good reason to keep your GPS receiver recording, even if you're not planning to do any surveying.
Apart from changes in the real world, your skill as a surveyor will grow the more you do...