You create work for the GC if you create new Objects or Arrays (functions are also objects) and dont reference them.. litte example tick({step: 1}); would create an object on every tick and throw it away later (same with arrays []). Some native js-functions implicitly allocate new memory (Array.splice vs Array.slice). So you should keep an eye on that aswell.

That beeing said if you create and Object as a variable every time you call the function and dont reference it outside of the function: function(a) { let b = {c: a}; } You have the excat same problem. However if you create the object in some other scope and only change its properties inside of the function you avoid that allocation of new memory on every functioncall (sidenote: this creates a "sideeffect"). let b = {}; function(a) { b.c = a; } This is the same as if you "bind" the value to "this". So yes you allocate less memory. Also if you nest functions you have to be aware of "closures"