This question raises an interesting issue that is explored in this text, and that is the way that different roles necessitate different skills and abilities. As a young warrior, for example, Beowulf as a character is able to desire personal glory without worrying about other people and how his actions will impinge upon them. When he is king, however, he is not able to act in the same way, and the text thus presents the reader with a tension between prowess and responsibility, between ability and ethical virtue. This is of course highlighted most strongly in Beowulf's decision to go and fight the dragon after he has been made king. For some Geats this is an incredibly reprehensible action, as the role of King means that Beowulf should think of his people first rather than his own glory and honour. Note the wise words that Hrothgar delivers to Beowulf after he kills Grendel's mother:
O flower of warriors, beware of that trap.
Choose, dear Beowulf, the better part,
eternal rewards. Do not give way to pride.
For a brief while your strength is in bloom
but it fades quickly; and soon there will follow
illness or the sword to lay you low,
or a sudden fire or surge of water
or jabbing blade or javelin from the air
or repellent age. Your piercing eye
will dim and darken; and death will arrive,
dear warrior, to sweep you away.
Arguably, Beowulf as a character proves that you can be incredibly strong and gifted with tremendous ability on the one hand, but not similarly endowed with ethical virtue. Although he proves himself to be an excellent warrior, his inability to escape the "trap" of pride, as Hrothgar refers to it, results in him continuing to seek glory as a king when ethically he should be seeking the protection of his people first and foremost, thinking of their long-stability rather than having one last effort at achieving personal glory.