Wtf

Typical in ideal models especially when gates are nowhere connected only to each other. At such small cap that those models offer and absolute inabilty to discharge electrostatic potential influenced from source and drain such potential is nothing unusual. In real device those tiny ammount of charges when hits few hundred volts will tunnel through insulation in moment or move away to neares neutralize place through safety zener that posses all mos devices. When this charge ammount will be a little higher a gate insulation will do not beign able to tunnel out such amount and at few hundred volts electrostatic potential breakdown occurs. for example when u touch gate by bare hand u can introduce typically 10kV of such potential when u walk on carpet made from polyesters or other such stuff and mos will never survive such as insulation became broken down cannot maintain e-fields of such magnitude. Todays mos have protecting diodes but they also cant protect at all situation so care should be always taken when operating on floating device without shorted all electrodes together.