'Summit' is one of several "success words" that have a strong tendency to occur in contexts of failure or frustration. Thus no Shakespearean character is ever on the right trail. "How my achievements mock me," Troilus exclaims in a sentence that epitomizes the usage of that word (Tro.4.2.69) "Inventor" is another boomerang word.
In keeping with this trend, summits are not something you climb, but something you fall from. So Rosenkrantz envisages "the cess of majesty" as
a massy wheel
18 Fix'd on the summit of the highest mount,
19 To whose [huge] spokes ten thousand lesser things
20 Are mortis'd and adjoin'd, which when it falls,
21 Each small annexment, petty consequence,
22 Attends the boist'rous [ruin]. (Ham.3.3.17-22)
And Horatio warns Hamlet against following the Ghost:
69 What if it tempt you toward the flood, my lord,
70 Or to the dreadful summit of the cliff
71 That beetles o'er his base into the sea,
72 And there assume some other horrible form
73 Which might deprive your sovereignty of reason,
74 And draw you into madness? (Ham.1.4.70)
Outside Hamlet, 'summit' occurs only in King Lear. Edgar assures Gloucester that he did indeed fall "from the dread summit of this chalky bourn" (KiL 4.6.57). Armstrong pointed out that the verb 'beetles' from the Hamlet passage returns in King Lear as the animal in the context of invoking the height of the summit:
How fearful
12 And dizzy 'tis, to cast one's eyes so low!
13 The crows and choughs that wing the midway air
14 Show scarce so gross as beetles. (KiL 4.6.11-14)
21 September 1999