Probability and chance can be mentally difficult to process, so humans are overly swayed by the allure of a lottery. For example, many people purchase lottery tickets even though the expected value of doing so is negative. As an extreme example, people spend $2 for a 1-in-292,000,000 chance of winning $50,000,000.
To encourage someone to do an action, consider creating a lottery with a cash or non-monetary prize.
Surveys frequently offer you entry into a lottery once you have fully completed the survey, with various prizes depending on the survey.
Lotteries do not have to have prizes that are cash (or cash equivalents) to be enticing for people. Prizes can be non-monetary rewards such as trips or sample products.