I can't tell you how mant times I put an rpg down and left it for months or years only to come back and forget what I was doing. I went and restarted the game to finally reach the same point and say, "Oh yea... thats the reason why I stopped playing." I proceed to do the same thing lmao. (Insert various FF games and other games in general with no blaring main quest banner blurb).
There are a few examples of games where it's even simpler if the game doesnt track quest progression. A designated button press for a character chat, characters comment on the current progess of the main story. They remind the player where to go in-character. Ex: Megaman Battle Network Series (extends to the Spiritual Sequels on the 3ds), Dragon Quest games.
Another example is a banner blurb in the menu "WE need to go here!" or what Tales of series games do. They have a summaries of the story chapters from the beginning and the current objective, in the form of little journal entries.
Quest Log in the screenshot is simple and easy to track~ Really nice. <_< Proceeds to download the game!