If you’d rather be doing something else, please go and do it. You are more useful there than here.
But if you really would rather be, say, drinking beer, you probably could be. Which means that actually you’ve chosen to do this instead.
So maybe you mean “Drinking beer is more immediately pleasurable than this, but instead I choose to do this because it’s more important / better for me / better for others / the right thing to do right now.”
Unless you’ve been coerced every step of the way, you’re playing a game. It may be a drudge, it may be a slog, it may not be your favourite thing to do, but in one way or another you’ve chosen it, and focusing on the beer you’re not having doesn’t make anything better.