The Left Angle Cross of Endeavor is named for Gate 21 and Gate 48. Human Design reads Gate 21, from Hexagram 21, Biting Through, sitting in the Heart or Will centre, as the will to control material life on one's own terms; and Gate 48, from Hexagram 48, The Well, sitting in the Spleen, as depth, a well of instinctive knowledge that is not yet useful, and a fear of being inadequate to what is asked. It falls in the Left Angle family, which practitioners read as fated in flavour, serving something beyond the individual rather than a self chosen plan.
Its design half is Gate 54 and Gate 53, both seated in the Root. Gate 54 is read as ambition, the drive to rise and transform one's material circumstances; it pairs with Gate 32 in the channel of Transformation. Gate 53 is read as the pressure to begin, an impulse that often has no interest in seeing a thing through; it pairs with Gate 42 in the channel of Maturation.
So a chart carrying this cross controls resources while sensing its own unspent depth on the surface, while beneath it a Root pair of rising ambition and raw beginning presses to be spent. The same four gates also underlie the Juxtaposition Cross of Depth and the Juxtaposition Cross of Control. The hexagrams are ancient; grouping them into one transpersonal cross is the modern system's own construction, dated to 1987.