They can still complete the challenge by consistently pushing towards the target on their own timescale.
For example, if one’s savings goal is £1,000, perhaps to be used for a holiday, they would only need to save £10 at a time.
For a larger savings goal, such as a house deposit, a larger saving would need to be set aside 100 times.
If a deposit of £10,000 wanted to be saved for, the saver would need to put £100 into their savings each time.
Taking up the challenge in order to save for a large sum such as this may make the process seem easier.