The use of alliterative verse in Beowulf suggests that the authors were likely following the traditional poetic forms of their time, as alliterative verse was a common feature in Old English poetry. It also indicates the authors' skill in working within these formal constraints and their desire to convey the epic story of Beowulf in a way that resonated with their audience.

Gawain

It creates a pattern that’s easy to remember (apex)

Pertaining to, or characterized by, alliteration; as, alliterative poetry.

Kemp Malone has written:

'Ten old English poems, put into modern English alliterative verse' -- subject(s): English literature