Tor has the goal of being high bandwidth and low latency, and relays on home connections can be problematic. Many home connections have rather low upstream band

Tor has the goal of being high bandwidth and low latency, and relays on home connections can be problematic. Many home connections have rather low upstream bandwidth, for example, so that circuits through such relays would be limited to few KB/s. The idea of having everybody be a relay is definitely tempting, but there are genuine engineering problems with it.