First torrent is not a database server that you can download files with your full speed....
It is the connection between computers to share data over internet...and these sharing takes place with peers....
So the main thing is what are the peers available for your file when your are downloading...
More the peers... more will be your speed..
Second is, it all depends on your internet pure download speed plus upload too...
You just cannot download torrent at 10 mbps speed with 10 mbps speed... you alsp need to have 10 mbps upload speed at the same time to gain download speed of 1 mbps
This is how torrent works..
So if you have 10 mbps download with 10 mbps upload then you can download at 10 percent speed at max
with good peers available the speed can go upto 2 or 3 i.e 20 or 30 percent
If you have 1 or 2 mbps like upload then i am sure you have download speed in Kbps...
So it all depends on various reasons....
Speed
File
Connections
Etc etc all