@EchoChamber maybe in your case it was the right thing to redecorate.
If everything looks really scruffy and run down, it can have a negative effect on buyers. They start noticing all the problems and assume the house will be a money pit of hidden disasters. In that case, a good clear out, a bit of basic redecorating to brighten things up and fixing some of the small niggly stuff can help.
Similarly, if the house is incredibly dated and everywhere a buyer looks is ‘I couldn’t live with that’ on their scale of home decor tolerance, then redecorating at least some of it will help. People generally do expect to redecorate but will often want that to be to their timetable, rather than something the feel they must do immediately because they really hate what’s there.
Repainting some walls can make an ugly carpet look less offensive, for example. And that might be the difference between potential buyers viewing the house as liveable but needing their own stamp rather than ‘total renovation’ in their mental model. That sort of thing will affect whether they’re even willing to make an offer. It might not affect what the offer is, they just won’t make one at all.