The construction of manufactured homes was not well-monitored until the mid-1970's when Congress passed laws that required builders of so-called mobile homes to conform to the fire and safety codes required of other home builders. Today, manufactured homes are considered much safer than they once were, but it is important to note that while he homes are built to higher standards they are still susceptible to greater amounts of damage when covered incidents such as fire or wind storms occur.
In many states, the law requires manufactured home to be permanently affixed to a concrete slab or held to the ground using tie-downs or other methods. The reason for this is that manufactured homes are much lighter than regular houses and can be blown over, or even completely destroyed, by high winds. Because of this, insurance companies charge higher rates for insuring manufactured homes to compensate for the increased risk of substantial payouts.
Another area where manufactured homes do not fare well is with fire. When a mobile home is hit by fire, it tends to suffer far more damage than other types of homes, up to including being completely destroyed in a matter of only a few scant moments. Because fire is such a serious risk and because fires can start from even a small spark outside the home, insurance companies view manufactured homes as a severe risk and have higher home insurance quotes to insure them. Water damage can be equally devastating for the same reasons.
So while it is true that manufactured homes are built to higher safety standards than they were, they still pose a higher risk to insurance companies. No amount of safety features can eliminate the risks of wind, fire or water damage, and where such damages could be an inconvenience to a regular homeowner they can be devastating to the owner of a manufactured home.