In most of the market situations, demand is always at a convex curve. When the prices are very high, there are still some consumers who wish and can buy commodities, and this contributes to the curve. On the contrary, when there are low prices, there exist very many consumers buying the products hence forming a curve. These mean that the demand level cannot touch either side of the x and y-axis besides a high increase in price or at low prices.

Some of the factors that contribute to this situation include an increase in income rates, where people get more salary; their purchasing power goes up, enhancing then to buy even at high prices. Primary products such as food also result in such a case where even if the prices are very high, there will still be people buying the commodities. Fashion goods also contribute to a convex curve where people wish to buy them at high prices. Similarly, when the prices are low, for example, during the sale of products at promotional bonuses, many people will be in a position to buy these products.