Last Minute

The Kozhnitzer Maggid says (second day Pesach) that even if one hasn't spent the days of Sefirah perfecting themselves, they can still make it up in the last day:

The last words of the mizmor of למנצח בנגינות that there is a minhag to say after counting the omer are אפסי ארץ.  This can be a remez to the idea of the Kozhnitzer; even one who is nothing, אפס, as low as the earth, ארץ , can still in the last minute become prepared for Shavuot.  The end of the אנא בכח that is also customary to say after counting is יודע תעלומות.  Hashem sees that in the depths of our hearts we want to be ready (R' Avrohom Schorr.)