One reason for light flickering

I know this is not about ST, but some users might run into the same problem and maybe should be aware of this. When I Installed a GE z-wave light switch, the lights in the whole house started flickering. The whole house! It turned out that the white neutral wire from the switch to the circuit neutral line was loose (I was lazy and did not secure the wire properly inside the nut). What surprised me is that it affected the whole house, not only the circuit that it was on. So lights on all other circuits were flickering. The message is: make the connections very secure. Thanks!