Please correct me if I have said something wrong, as it might be the answer to my question. Also, these are all the things that I've learned through self-studying, so I might have been mislead.
The plate tectonics theory states that the Earth's lithosphere have been and is still (slowly) moving since about 3.4 billion years ago. It is proved by many evidences, most notably global distributions or locations of volcanoes, earthquake epicenters, and mountain belts. When superimposed, these locations somewhat forms the plate boundaries of a proposed supercontinent pangea.
From my understanding, volcanoes, earthquake epicenters, and mountain belts are all the products of colliding plates.
If this is so, and if it is true that the plates moved somewhat away from each other (since it was once a supercontinent, then it is now scattered), then why is it that there are volcanoes, earthquake epicenters, and mountain belts--products of collision--in areas where a collision didn't happen?
Like, the plates moved away right? And collision, from my understanding, is the crashing of two plates, and collision ≠ moving away. So why is it that they formed despite no plates collided to each other?