What's a good German translation for ".. you'll be such a bad loser"?

Question

The English sentence is:

If you do something like that, you'll be such a bad* loser.

Meaning that you'll lose badly.

I translated it as:

... Du bist ja ein schlechter Verlierer.

But someone told me, don't use "schlechter" but "guter" instead. Who's a "schlechter Verlierer" and who is a "guter" one? Is there a better translation for what I'm trying to say?

_{*: What I meant is not that the person as a bad loser, becomes angry when they lose but preventing them from doing it by using the word "bad".}

Answer 1

In the meaning you added in your footnote "schlechter Verlierer" is not the appropriate translation. Let me give you some interchangeable variations on how to say what you meant (translations for "bad" in italic):

Wenn Du so etwas machst, wirst Du übel verlieren.
Es wird böse enden, wenn Du dies machst.
Wenn Du so weiter machst, wird das schlecht ausgehen.
Dein Vorhaben wird ein schlimmes Ende nehmen.
Du bist ein elender Versager, wenn Du das machst.

The last example is quite strong and as such may be considered as rude.

Answer 2

I think you mean "to lose badly".

Wenn du so etwas machst, dann wird das übel für dich ausgehen.

"Übel"

In that sense it means a bad outcome and "für dich ausgehen" puts emphasis on the personal consequences.

Answer 3

"You will" be is future tense, So that can't match "Du bist", which is present time.

Wenn Du das tust, wirst Du schrecklich (furchtbar, übel, schlimm, empfindlich, haushoch (v.a. im Sport)) verlieren!

I guess it is a recent development, to brand somebody "Verlierer" or "Loser" in German:

Wenn Du das tust, wirst Du ein Verlierer sein.

"Schlechter Verlierer" is the terminology for a person who cannot stand losing a battle, a fight or a game. So you would avoid such attributes to emphasize the meaning, as you mentioned yourself.