When Hakadosh Baruch Hu brings a neshamah to this world, Hashem sends it down via a very long ladder that extends from heaven to earth. After the neshamah reaches earth, Hakadosh Baruch Hu takes the ladder away and says, “Now climb up again on your own.” ~ The Kotzker Rebbe zt”l
Rav Biderman says that some neshamos give up immediately. Others jump, but when they fall back down, they give up. However, some jump and jump, again and again, until Hakadosh Baruch Hu has mercy on them and brings them up to heaven. Because when a person tries, Hashem will help him.