ところだったWas about to; almost
ところだった looks back at a past moment when an event was just about to happen. Context often shows that it did not happen, producing the meaning “almost,” but nonoccurrence is not built into the form itself.
The key is the past viewpoint
ところだった places the viewpoint immediately before an event, then looks back at that stage from later. In many cases something prevented the event, but it can also simply introduce what happened while someone or something was about to act.
Three common contexts
The surrounding details tell you whether this was an avoided danger, a missed opportunity, or an interrupted plan.
危うく階段から落ちるところだった。
I nearly fell down the stairs.
Analyze危うく makes it clear that this was a narrowly avoided danger.
私はあと少しで優勝するところだったのに、最後の直線で追い抜かれた。
I nearly won, but I was overtaken in the final straight.
AnalyzeHere the nearly realized event was desirable, and the ending expresses disappointment.
私はちょうど家を出るところだったが、上司から電話がかかってきた。
I was just about to leave home when my boss called.
AnalyzeThe call interrupts the about-to stage. The sentence does not claim that the speaker never left later.
Words that strongly signal a near miss
危うく, もう少しで, and あと少しで strongly favor the “almost happened, but did not” reading. Without such a signal, look for an interruption, a changed outcome, or other contextual evidence.
About to now versus about to then
ところだ presents an action as about to happen at the current reference moment. Adding the past ending gives ところだった, which looks back on that same about-to stage from a later point.
私は今から出かけるところだ。
I am just about to go out.
AnalyzeMore examples
ブレーキが少し遅れていたら、前の車にぶつかるところだった。
If the braking had been slightly later, the car would almost certainly have hit the vehicle ahead.
Analyze会場に着いたとき、式が始まるところだった。
On arriving at the venue, the ceremony was just about to begin.
AnalyzeThis describes past imminence; it does not suggest that the ceremony was canceled.
店員が声をかけてくれなければ、傘を置き忘れるところだった。
If the clerk had not spoken to me, I would have left my umbrella behind.
Analyze彼女は発表を始めるところだったが、機材の不具合で延期になった。
She was about to begin her presentation, but it was postponed because of an equipment problem.
Analyze私たちは決勝に進むところだったのに、最後の問題で逆転された。
We nearly advanced to the final, but the other team came from behind on the last question.
Analyzeメールを読み返さなければ、日付の間違いに気づかないところだった。
If I had not reread the email, I would have failed to notice the incorrect date.
AnalyzeThe negative verb shows that the nearly realized outcome was a failure to notice something.