You have the option to choose the 'Next Best Seller' option when there is competition below your Minimum price.
This means that RepricerExpress will reprice you against the next cheapest seller above your Min.
Sometimes, it can happen that there is no Next Best Seller or there is one is above your Maximum price. In this particular scenario, your SKU will not follow the 'If there is no competition' scenario but will go to your Min price.
If there is a 'Next Best Seller' above your Max price and you would like to compete with them, you should increase your Max prices.