As our watch ranking indicates Patek Philippe is in a whole different category when compared to Rolex.  While Rolex is the most well known watch brand in the world, Patek Philippe is at a whole different level of sophistication and class.
Rolex is great because it makes everything in its watches in-house and at the highest level of quality.  They achieved remarkable quality levels even though they mass produce watches.  They build a great product and were very successful to market their brand name worldwide.
Patek Philippe also makes its parts in-house, but they go the above and beyond.  Patek Philippe's watches are much more refined in terms of detail in the movement and in complications.
For example they polish every part in their movement whether it is visible or not.  Also, they've kept records of every watch they made and as a result are the only manufacturer who can restore any of thir watches - even those dating as far back as 1839.  With a Patek Philippe you know you're getting the finest possible craftsmanship.
While everyone in the world knows about Rolex only those with some horological knowledge know about Patek Philippe.