{{{1}}} Nodes will only fire if {{{3}}} has seen the value on their local machine {{{2}}}. When this node sends impulses from {{{3}}} across the network it can be used to execute code that requires the impulse be from a specific user, like changing worlds, knockback, writing unsafe cloud variables, and other Local User sensitive nodes. {{{1}}} Nodes also check the value every game tick. If you're doing checks that require lots of calculations, it may be better to monitor a value that requires less processing power to calculate, or a value that doesn't change that often, and then check the rest of the conditions you were checking before on an If node, since those only check their argument when impulsed rather than every tick.