Flash transistors are merely cmos field transistors, except that the gate made of silicon dioxide can be charge injected or stress relieved. this put the transistor permanently in the preferred state of 1 or 0. A persistent memory without electricity to maintain the data. You can rewrite the data by flowing the gate oxide, or relieve the charge of electrons.

This function is designed by doping of the silicon oxide gate. The first ones use 12 volts to write the gate. Then it was reduced to 5 volts to write the gate to 1 state. Today the transistors are so small that that gate sensitivity is very much reduced to less than 1 volt to write the gate.

When you use the flash transistors, you should be careful that the voltage spikes are not present when you shut down power unless you know that the flash drive has buffers to suppress the inductance kick. Many older flash drives are unreliable because of inadequate buffer capability.

Alpha particle charges may corrupt your flash drive? Possible if transistors are encapsulated by ceramic case. If it is plastic encapsulated, alpha particles can not penetrate to the gate of the transistor. this is because of the unique properties of carbon hydrogen absorption coefficient.

If flash transistors have problems, you may try to anneal the drive by letting it warm up in the powered on circuit. Low temperature will anneal the gate of the transistor and it will resume working until it cooled down again. Some times you can get lucky, but keeping the power on will continue to keep flash transistors working indefinitely.

Some of the reason that people argue that if you never shut down electronics, they will work better and mean time between failure will be very lengthy.
The reason is you avoided stress due to thermal coefficient of expansion putting transistor gates stressed or even cracked, which needs reflow of the oxide to cure it.

Typically, high powered cmos amplifiers need an hour of warm up to run without distortion. Flash memory sometime require a period of up to 5 minutes warm up to run without data errors. The transistor size determines the warm up time needed. Smart Linux distro developers will use checksum before allowing Flash drives to be used.

Footnote:
When cmos transistors cooled down. Silicon shrank, but silicon dioxide did not shrank as much due to the difference in thermal coefficient of expansion. There will be residual stress between the two dissimilar material, and the transistor will have a short, when it should have been normal and open. When the transistor warmed up, the stress will be gone, and the transistor will be normal either 0 or 1 state depending on the gate signal written. When you run cmos long and temperature went up higher, sudden cool down will take longer period of warm up for sure. So, the analysis is to run flash drive with reqular warm up period and shut down as soon as you stop using it. This will keep the length of warm up periods manageable.