Question

Why does the TC curve start from the Y-axis and TVC curve from the origin?

Answer 1

The Y-axis is where the Total Cost (TC) curve begins because, even in the case of zero output, the company must still pay fixed expenses like rent, permanent employee wages, insurance, etc. These expenses are inevitable and must be covered regardless of production volume. Because of this, the TC curve starts on the Y-axis at a positive point. 

However, since the company does not have to pay for raw materials, additional labour, or electricity if no output is being created, the Total Variable Cost (TVC) curve begins at the origin (0,0). Since production directly affects variable costs, they are also zero when output is zero.