Back on the ship from land

[Flushhdraw]

I play the game on Steam and I noticed that sometimes when I've been on the land to get a treasure or find my sister or whatever and I go back to the ship all I have to do is hit enter and it shows my guys actually walking on board which is pretty cool but other times the only way you can get back on the ship is to click return to ship even though the ship is right in front of me. Any idea why it does this??