If a dartboard gets wet, it can become damaged and potentially unusable. Many dartboards are made from sisal or bristle material that can absorb water and become warped or uneven, which can affect the accuracy of throws and make the game less enjoyable. Wet sisal bristles can also swell, causing them to pull loose from the glue layer and fall out of the board. Additionally, if the darts become wet, they can rust or corrode, and if left on the board for too long, they can start to warp. Therefore, it's recommended to keep dartboards dry and avoid damp areas or humid spots where you hang the board. If the dartboard does get wet, it's essential to dry it thoroughly as soon as possible to prevent damage.