Irṣād may draw on two basic clues: a previously mentioned root or expression and a semantic progression that calls for a particular conclusion. A known rhyme consonant in verse can provide an additional constraint.
ClueEffect
Lexical memoryli-yaẓlimahum prepares yaẓlimūn
Semantic completionInability leads toward ability
Verse rhymeRestricts likely endings
These clues may work separately or together. They make the ending a fitting resolution instead of an arbitrary final addition.