Why does led lamp not close properly?

With a slightly light after close led lamp, why does led lamp not close properly? the mainly reason is the electrification of zero line. that does happened very often. the problem from installer. they didn’t operated according to the correct operation rules. they didn’t put the live into electrical plugs (electrical plugs have one live wire , one neutral wire and one earthe wire)，and control switch with neutral wire.   although the switch is off, But live wire still have a little current is flowing. that make that the led lamp has a slightly light. solution: adjust the electricity wire position and direction for the best status of control.

If led lamp is a slightly light, call a repairman immediately. then you  would like to tell me what happened