Learn Hardcore Korean: silsu-igin hajiman da-eumeneun deo jalhamyeon dwae. - It may be a mistake, but next time we can do better.

실수 + 이다 + -기는 → 실수이기는 → 실수이긴 It acknowledges something as true (“It is a mistake”) while downplaying it to contrast with what follows (“…but…”). Natural English feel: “It’s a mistake, yes, but…”

Why do we have both -이긴 and 하지만? Aren’t they redundant?

They often come as a pair: -긴 … 하지만.

-긴 flags concession (“it’s true that…”).
하지만 introduces the counterpoint (“however/but…”). You can drop 하지만 in very casual speech, but keeping both is smooth and clear.

Can I say 실수하긴 했지만 instead? What’s the difference?

Yes.

실수이긴 하지만: noun + copula; labels the situation as “a mistake,” neutral about time.
실수하긴 했지만: verb-based and explicitly past (“did make a mistake”), more event-focused.
Both are fine here.

What about 실수였긴 하지만? Does the tense matter?

Grammatical and natural. 실수였긴 하지만 highlights the past state (“it was a mistake”), but Korean often uses the nonpast 실수이긴 to talk about a past event without awkwardness. Choose based on how strongly you want to mark pastness.

What does 다음에는 do? Why add -는?

다음에 = “(at) the next time” (locative -에).
Adding the topic -는 gives 다음에는 = “as for next time,” setting up a contrast with now.
Colloquial contraction 다음엔 is very common.

What exactly does -면 돼 mean?

It means “it’s enough/OK if …; all you need to do is ….”

-면: if/when
되다: to become; to be OK/allowed/sufficient
So 더 잘하면 돼 = “You just have to do better (and that’s sufficient).” It often sounds reassuring.

Is 돼 the same as 되? I see both.

They’re related forms of 되다, but the spelling here is fixed:

Informal: 돼 (not “되”)
Polite: 돼요 (not “되요”; it’s 되어요 → 돼요)
Formal: 됩니다

What politeness level is this? How do I make it polite or honorific?

The sentence ends in informal …돼. More polite options:

Standard polite: …돼요 → 실수이긴 하지만 다음에는 더 잘하면 돼요.
Formal: …됩니다 → 실수이긴 하지만 다음에는 더 잘하면 됩니다.
With honorific to the addressee: …잘하시면 돼요.

Who is the subject here? Why isn’t “you” stated?

Korean drops subjects when clear. With -면 돼 (advice/reassurance), context implies “you.” To make it explicit:

Very casual: 너는 다음에는 더 잘하면 돼.
Polite with a name/title: OO 씨는 다음에는 더 잘하시면 돼요.
Avoid 당신 in most situations; it can sound blunt.

Is 더 necessary? What nuance does it add in 더 잘하면?

더 = “more/better (than before).”

With 더: “Do better than last time.”
Without 더: 잘하면 돼 = “Just do well (next time).”
Both work; 더 highlights improvement.

Could I replace 하지만 with 근데/그런데?

Yes. 근데/그런데 is more colloquial and softer. You’ll also hear -긴 한데:

실수이긴 한데, 다음에는 더 잘하면 돼.
근데 실수하긴 했어도, 다음엔 더 잘하면 돼.

Can you break down the sentence morphologically?

실수: mistake (noun)
이: copula from 이다
-긴: contracted -기는 (concessive/topic emphasis)
하지만: but/however
다음에: at the next time
-는: topic marker → 다음에는
더: more
잘: well
하면: if/when (from 하다 + -면)
돼: is OK/it suffices (from 되다)

Is there a softer, more encouraging way to phrase it?

Add softeners like -지, 요, or reassurance:

실수이긴 하지만, 다음에는 더 잘하면 되지.
실수했어도 괜찮아. 다음엔 더 잘하면 돼.
Polite: 실수였긴 하지만, 다음에는 더 잘하시면 돼요.

Does -면 돼 also express permission?

Yes. It covers “sufficiency” and “permission.”

지금 가면 돼. = “You may go now/It’s fine if you go now.”
이거만 하면 돼. = “You only need to do this.”
In your sentence it’s the “sufficiency/advice” reading.

Is 실수긴 하지만 (omitting 이) okay?

In casual speech, yes. 실수긴 하지만 is common and natural. 실수이긴 하지만 can feel a bit more careful or written. Both are acceptable.

Difference between …하면 돼 and …하기만 하면 돼?

…하면 돼: Doing it is enough.
…하기만 하면 돼: You only have to do that (adds exclusivity/emphasis).
So 다음에는 더 잘하기만 하면 돼 sounds a bit stronger: “All you need to do is just do better next time.”