Most experienced builders already know the greenery pieces that are used to cover this wreath don't lock as tightly together as Lego bricks do, so it should come as no surprise that they pop off / fall off the wreath VERY easily. Same is true of the red and white accent balls. It may not be as big a problem for those who build the tabletop version.
This piece is definitely for use indoors only, and only in a location where it won't be touched or even get any strong bumps or vibrations. I wish it were more sturdy; I'll worry about pieces falling off of it all holiday season long. ='/"