YOU SAID:

If you don't try you'll never fail

INTO JAPANESE

試さないと失敗することはない

BACK INTO ENGLISH

You won't fail unless you try

INTO JAPANESE

試さない限り失敗しない

BACK INTO ENGLISH

Don't fail unless you try

INTO JAPANESE

試さない限り失敗しないでください

BACK INTO ENGLISH

Don't fail unless you try