Omission bias means that we often make decisions based on what can be taken away rather than on what is added. That is, we are more likely to choose an option if it doesn't involve something bad happening. For example, if you were deciding between two investments, you might be more likely to pick the option that doesn't include any losses, even if the other option had a greater potential reward. Omission bias is a way of thinking that can lead to us favoring situations that, while they may be safer, don't necessarily give us the best outcome.