If you plan to have your wedding dessert displayed  prior to your guests eating their main meal and are concerned whether they will want to take a bite, having a dessert sign is a great idea to keeping your guests away until the appropriate time.  Most weddings are providing candy bars and cupcakes for the dessert portion of the evening and can take sometime to set up, so it only makes sense to have it ready to go before the guests enter the room. also consider that the wedding photographer will want to get some pre-shots of the room as well and will want everything looking as clean as possible.