Using slice remove last two characters from given string

The basic syntax for the slice is 

array.slice(start, end)

The sample string is 

var text = "welcome!";

Now, i am trying to remove last character from the above string using slice.

text = text.slice(',',-1);

Now the result is : welcome

Slice is also used for remove values from array, here is the example.

var fruits = ["Orange", "Strawberry", "Banana", "Orange", "Mango"];
var myBest = fruits.slice(-3, -1);

the result is 

Orange,Lemon