Overtime, your Rolex clasp will begin to loose its tight fit. This common issue is actually resolved quite easily. Here is a "how to" on how to make that Rolex clasp feel tighter or looser for that matter. First, undo the entire clasp. As you can see, we have an example of the Everest Oyster clasp, but our clasp is based off a Rolex Oyster clasp. So for example purposes, this is perfect.
Second, very lightly bend the connecting butterfly piece between the buckle itself and the butterfly connecting to the 6 o'clock link side. Notice the picture below.
To tighten the clasp, bend the butterfly piece to create more of a curve. To loosen it, flatten the butterfly piece by bending it the opposite direction.
Hopefully, this helps create a perfect fit and makes that Rolex clasp feel new again!