Of course it is. Even if it doesn't matter on your machine, your users will launch your code:
* on a 10 years old PC
* in train on a laptop with 10% battery left
* on a computer with so many things running in the background that you'll be on the edge of thrashing
* on a thermally throttled ultrabook
* on an underpowered SBC
* through foreign CPU arch emulation
* [insert more cases here]
In each of those scenarios, your code will either do its job well or be the source of frustration.
Of course it is. Even if it doesn't matter on your machine, your users will launch your code:
* on a 10 years old PC
* in train on a laptop with 10% battery left
* on a computer with so many things running in the background that you'll be on the edge of thrashing
* on a thermally throttled ultrabook
* on an underpowered SBC
* through foreign CPU arch emulation
* [insert more cases here]
In each of those scenarios, your code will either do its job well or be the source of frustration.