http://revach.net/article.php?id=3432

Section: Shira   Category: AlephBais
Aleph is for Adam
The Medrash Pliah asks how is it that Adam came to do an aveira?  The Medrash answers he saw two but did not see three.  The explanation of this riddle says the Gaon HaKadosh ofShiptivika (See Yalkut Niflaos: Adam HaRishon) is the Mishna in Pirkei Avos (3:1).  Akavya ben Mahalalel says if a person keeps in mind three things he will not do an aveira.  He must remember his humble beginnings from a tiny drop, his lowly end in the dirt with worms, and his ultimate accounting before Hashem.

Adam HaRishon had a glorious roots.   He was the Yetzir Kapav, the labor of Hashem's own hands, kviyachol.  He only had two things to think about before doing an aveira.  He was missing the third piece of the puzzle, like the Medrash says.  Therefore he stumbled in his ways.