If you regularly work with clients, you're going to evolve how you work with them over time.
This might sound like overkill, but I recommend reviewing your contract with every two to three clients you sign. Reviewing your contract every few clients helps you hone in and tone up your contract so they are rock solid.
You know just how much your work changes as you learn more about your skillset, what your client needs, and what you like/don’t like/really excel at providing. You also get more experience under your belt, and learn more about deadlines, turnaround times, client troubleshooting, and so on.