There are many reasons why people might think that they are unlucky. Here are a few possibilities:
Confirmation bias: People tend to remember negative events more vividly than positive ones. This can create a sense of being unlucky because they only focus on the negative events that happen to them, while ignoring the positive ones.
Superstitions: Some people believe in superstitions, such as the idea that walking under a ladder or breaking a mirror brings bad luck. If they experience any negative events after performing such actions, they may attribute it to bad luck.
Lack of control: People may feel unlucky if they feel they have little control over their lives or the events that happen to them. This can lead to a sense of powerlessness and the belief that bad things always happen to them.
Comparison with others: When people compare their lives to others, they may feel that they are less fortunate or unlucky in comparison. This can lead to a sense of unfairness and the belief that they are unlucky.