I think that avoidable cost is the cost that can be avoided if certan decision is taken or not taken. It is more or less cost which is varied according to the decision taken by management. That is...
When considering outsourcing a portion of services provided, avoidable costs are those that would go away if the service was outsourced. Unavoidable costs are those that would remain such as overhead.
Unavoidable cost ; inescapable cost ; sunk cost. Unavoidable costs will occur whether the decision is made to go ahead or not, because the firm has already spent, or committed to spend, the cash.
ยท Normal loss is unavoidable losses arising due to the nature of the material or the process
The reasons for such loss in output can be due to the following: Evaporation; Breakage; Scrap due to...