Understanding why we buy things helps us see how people behave as shoppers. There are a few important areas that affect our buying choices:

1. Personal Factors

• Income Level: How much money we have affects what we buy. A survey in Sweden found that about 60% of shoppers said their income really matters when they go shopping.
• Age: What we like to buy often changes as we get older. For example, younger people might care more about what’s trendy, while older folks usually look for quality and how long something will last.

2. Psychological Factors

• Perception: How we view products influences our decisions. Studies show that 85% of shoppers trust online reviews just as much as recommendations from friends.
• Motivation: According to a famous idea called Maslow's Hierarchy of Needs, we need to meet our basic needs, like food and safety, before we think about things that boost our self-esteem.

3. Social Factors

• Peer Influence: What our friends and family say can strongly affect what we decide to buy. One study found that 70% of people often ask their friends or family for advice before making a purchase.
• Cultural Background: Our culture shapes what we want and what we think is valuable. For example, a report showed that 72% of Swedish shoppers prefer buying local products, showing they want to support businesses in their community.

4. Economic Factors

• Market Trends: Economic situations can change how we shop. During tough times, about 62% of shoppers say they become more careful with their money and focus on buying just the things they really need.
• Inflation: When prices go up, people tend to change their shopping habits. Studies say that 57% of consumers change how they buy things when prices rise.

5. Utility Maximization

• When we shop, we try to get the most satisfaction from what we buy. We think about whether the extra enjoyment we get from buying one more item is worth the cost. This idea can be simply shown like this: $\text{Maximize satisfaction } = f(\text{quantity})$

In summary, our buying decisions are shaped by personal, psychological, social, and economic factors, along with the idea of wanting to get the most value for our money. These factors work together to influence how we shop and what we choose to buy.