Teshuvah - Hard or Easy?

Teshuvah is called "very close to you, in your mouth and in your heart," and the Ramban reads that pasuk as being about teshuvah. Yet look around, and look at ourselves: it hardly feels easy. Why would the Torah testify that it is? A mashal of prisoners who dig their way out of a cell has the one who stays behind in trouble, and a question that has bothered Rabbi Asaf Prisman for years about why the comparison works. Rav Chaim Shmulevitz points to what really stands in our way before Rosh Hashanah.