Answer:
Decline of learning
Step-by-step explanation:
During the period leading up to the fall of roman empire, most of the people spent most of their money to work and survive. Leaving very little chance for them to spent their time and resource to pursue education.
Because of this, the development in Rome became stagnant. They couldn't keep up with the more modern inventions that other empire use in agriculture, warfare, and transportation. On top of that Roman citizens did not possess enough aptitude to develop something that could improve romans' economy.