Broken Arrangements

Mistakes sometimes happen, plans sometimes change
People get ill and things rearrange
But it seems that more often, people drop out
Of events they've accepted, are no longer about 

Perhaps they didn't really want to go 
But in that case, why didn't they just say no
Maybe they just forgot to diarise 
It was not that important in their lives 

Will someone please tell why it's seems so hard
To get a commitment, or to keep to one’s word
It's tiring to keep setting up social engagements
When so often they end up as broken arrangements