To the average voter who doesn't follow things very closely, the options were basically:

• bad, but the same as the previous admin, which did stuff that negatively impacted me
• bad, but different; the last time they were in office, they didn't do things that impacted me too much

Unfortunately, far too many people blame the economy on the sitting President, when they often have little influence on it. Trump was president during an economic boom, and got out just as COVID was going. Biden was president through COVID, and by all accounts was incapable of the job during at least part of his term. What do you expect the average person to do who doesn't follow politics closely but catches bits and pieces closer to the election? Of course they'll go with the person promising change over the person promising the status quo...