Why downloading speed is greater than uploading speed?

Why downloading speed is greater than uploading speed?

Its main reason is that most high speed Internet connections including cable modems and DSL are asymmetric. Asymmetric means that any one packet of data can either go in, or out, but not both ways at the same time.  They are designed to provide much better speed for downloading than uploading because most users spend much more time on downloading the contents available on the Internet than they do uploading. So, Internet service providers have designed their systems to give priority to downloading that is why, for many users uploading files is quite a bit slower than downloading file