Understanding Effect.isFailure with Effect.succeed

I see people waaaay more smart then me here, so could some one explain me why does this condition is true?

import { Effect } from "effect"

if (Effect.isFailure(Effect.succeed(1))) {
  console.log("is Failure");
}

import { Effect } from "effect"

if (Effect.isFailure(Effect.succeed(1))) {
  console.log("is Failure");
}

Understanding Effect.isFailure with Effect.succeed - Effect Community