why do some people do
local value = false and -1
These identifiers are known was “idioms” and act as if statements. What your code does is if value is false, set it to -1.
If I wanted to check if a value is 5 and set it to 10, if it is. I can do that by if statements and idioms.
I’ll do it with idoms:
local val = 10
val = val == 10 and 5 or val --> if val is 10, set it to 5 or to val(5)
The reason for the or is because if val is not 10, it will be set to what it is currently. You can’t expect val to be 10 all the times and if it isn’t, val will be set to false because the idiom evaluated to false.