For when i would account to myself for the birth of that passion, which afterwards ruled my destiny, i find it arise, like a mountain river, from ignoble and almost forgotten sources; but swelling as it proceeded, it became the torrent which, in its course, has swept away all my hopes and joys.

https://www.cliffsnotes.com/literature/f/frankenstein/summary-and-analysis/chapter-2/chapter-2-2

glamis thou art, and cawdor; and shalt be what thou art promis'd; yet do i fear thy nature; it is too full o' the milk of human kindness to catch the nearest way: thou wouldst be great; art not without ambition; but without the illness should attend it. what thou wouldst highly, that wouldst thou holily; wouldst not play false, and yet wouldst wrongly win: thou'dst have, great glamis, that which cries, "thus thou must do, if thou have it: and that which rather thou dost fear to do than wishest should be undone." hie thee hither, that i may pour my spirits in thine ear; and chastise with the valor of my tongue all that impedes thee from the golden round, which fate and metaphysical aid doth seem to have thee crown'd withal.  

he lacks ambition.  

he is hesitant.  

he lacks courage.  

he has moral scruples.

teenagers are certainly stereotyped as moody.

most people view teenagers as naturally moody and grumpy, even when this is wrong. many teens are suffering from depression but it is brushed off as "just a phase" or "that's just cause they're a teenager"