Block form

When you create a custom block, neither the title nor the body are required, only the description. Blocks without content don't show up - which means you can put the empty block in a region, and there's no indication of why it's not there.

There is no help text on the Page specific visibility settings (blocks/configure).

A user created a block, but did not enter a title or body so they could just see what it would look like. However with both values empty, the block is never actually shown even if it is enabled.

Users expected to have to enable a block. Users did not unite moving a block from the disabled block area to a region as enabling.