Torrent download speeds depends on two factors
1. The number of seeds
2. The number of leeches
The higher the number of seeds, the faster your download. The
reverse is true if the number of leeches is high.
At different times of the day, there are different number of people
seeding or leeching, which resulted in a fluctuate.
As for why it's slow... it's caused by the seeding and leeching as
well. Because it's a peer-to-peer technology, everybody is a server
as well as a user. You as a server is limited by your ISP.
For direct downloads, it's faster because more bandwidth are
generally allocated to them, plus it's their purpose to serve, not
do other things, which speeds up things a lot.
