$1.$Why do we need an estimate of Bad Debts?$$

$2.$Why do we have a new account, called Allowance for Doubtful Accounts? What does this account represent?$$

$3.$How are the allowance method and the direct write$-$off method different?$$

$4.$

Why isn't the Direct Write$-$Off method accepted under GAAP?$$

$5.$ How can someone manipulate $($cook$)$ the books by providing a wrong estimate?