What will happen to untreated wood if it is left outside?

Untreated wood left outside will be susceptible to various environmental factors, leading to deterioration over time. It can absorb moisture, promoting mold and rot, while exposure to UV rays can cause fading and cracking. Insects, such as termites and wood-boring beetles, may also infest the wood, further compromising its structural integrity. Ultimately, untreated wood will degrade more quickly than treated wood, significantly reducing its lifespan.