and on the next line of code, i could be totally different values each time 'through the loop'. 'looks' or 'feels' like i will only ever have the first value it is assigned. So you can start to see the dissonance between an 'i' that changes (or is redefined) potentially thousands of times per second as you iterate through a list and for(const i. ie for(const i=0 i<50 i++) throws an error. And this was even true in JavaScript since it's inception with 'var', and is still true when you do a simple for(let i=0 i<50 i++). The 'i' typically ends up being a 'register variable' on the CPU itself (not in RAM) so that it can 'change faster'. Nothing gets it's value changed more than the 'i' in all the for loops. The variables in loops (at least in most C-like syntax languages which JavaScript is based on) are the variables that change THE MOST. For example, having const server = '' in one place, and const server = '' in another place would be 'objectionable'. But they further feel awkward 'redefining multiple constants with the same name'.

Many people see const as a 'constant' which should never change. There is a simple reason for the prevalence of for(let i instead of for(const i among even experienced devs/tutorial makers who are not modifying the value in the loop body and understand const/let.

Javascript for of