The reason to bother at all rather than shrug: droppings spread coccidia and bacteria, and a wet brooder with droppings trodden through it is how a batch gets ill. A few pecks will probably do nothing. A dirty brooder is a different bet.
What I watch for after losing two: diarrhoea or blood in the droppings, lethargy, anybody off their feed, weakness or trouble walking, and poor growth against the others. Any of those with poultry and it is a phone call rather than a clean-up.