The presumption of innocence combined with the "beyond a reasonable doubt" standard of proof means that, in a wide variety of criminal cases, the defendant is quite possibly or even very likely guilty but there is still reasonable doubt.

That means that the finding is necessarily something we call "not guilty," as that's the literal finding of the court. We do not find you guilty and this matter is closed. It is not a finding of innocence and so is not reported as such.

Simplistically, compare the difference in the NFL replay system of "the ruling on the field is confirmed" vs "the ruling on the field stands". The latter is the gray area and both are reported as "not guilty" in the criminal system (in the US).