Why do accountants process adjusting journal entries?

Why do accountants process adjusting journal entries? You over hear a conversation between two Accounting for Business students. One student comments that “the effect of adjusting entries is either immaterial or non-existent overtime" is this correct? If so why should accountants botherwith the extra ‘work’ involved with the adjusting process? Use an example to illustrate your answer.should be sufficient to effectively answer this question.