There is a coat of marmalade that prevents the ingredients from being brought down and prevent flow to the bottom section of the board.
In the columns where the ingredients spawn, there is popcorn. This can be considerably hard to remove.
Bringing down the ingredients in the first and ninth columns could be extremely difficult if you're not planning on switching. The blockers are separated from the majority of the board, and there's also hard-to-reach popcorn in those columns.