The simplest way to see this in action is the print the increment directly to console.
//declare a variable and assign it a value
int x = 0;
//so here jn the println method we use the original value and print it, straight after it uses the value of x it then increment it by 1 but you dont see this until next time you use x.
//⬇️here the value of x is now 1 because as soon as x was used in above method straight after the value increased by 1