This game's not bad at all. It just feels super aggressive as far as hit detection, although I noticed it's actually not unfair, it just feels that way because of the slipping and sliding and the fact that it instantly teleports you back to the start. All these factors combined make the player's brain register failure before registering hitting a hazard. You could mitigate this by playing some sort of short flashing animation on the character for a split second before moving them back to the beginning, so the player can indeed confirm that they were out of bounds.