why 'const' is considered better than 'let' and 'var'

Some reasons why const is considered better than let and var in certain situations:

1. 'let' and 'var' values can be reassigned but the 'const' value cannot be reassigned once it has been initialized, which can guarantee that the value of a 'const' variable will not change and prevent unexpected behaviour in code.

2. It prevents bugs due to accessibility within the block it was defined in(block scope).

3. It can improve performance because the JavaScript engine can optimize the code better when it knows a variable will not change.

So, 'const' is a good practice and can help make your code more robust, readable, and maintainable. Also, there can be situation comes for using let then definitely we will go for 'let'