Can frequent erasing of USB flash drives cause damage

I think it is not so much a USB not being bootable but if the MB can recognize it and boot from it.

Motherboards of today should all be supporting USB booting. With that being said all of today's USB drives should also be capable.

I have heard of people flipping the removable bit on their USB to make it look like an actual disk drive. This can help the bootability of the USB (I think, but it is only needed on older systems that cannot recognize it). You do need to flip this bit if you want to have windows recognize multiple partitions on the USB.

It is recommended that said USB has decent read/write speeds to improve bootability.

Here is a discussion in another forum that is about your question.

If you are still unsure if your MB or USB are suitable for USB booting I am certain that Google can answer all questions about a specific product.

Here is a paper about errors caused by power failure on flash memory: http://cseweb.ucsd.edu/users/swanson/papers/DAC2011PowerCut.pdf

I cite the last sentence of the abstract:

Finally, we show that incomplete erase operations make future program operations to the same block unreliable.

and the conclusion of the paper:

The flash memory devices we studied in this work demonstrated unexpected behavior when power failure occurs. The error rates do not always decrease as the operation proceeds, and power failure can corrupt the data from operations that completed successfully. We also found that relying on blocks that have been programmed or erased during a power failure is unreliable, even if the data appears to be intact.

My personal conclusion is

• Power loss in general can render flash memory in an unreliable state. However, once you hard erase, the memory works as good as before.

• Carefully written firmware can fully prevent errors on power loss but at a performance and lifetime cost of the flash memory as writes have to be protected by extra writes.

• Many vendors offer hard erase utilities for download. But I think there are flash memory devices that do not allow you to do a hard erase and also will not perform a hard erase themselves and also do not employ a perfectly safe write protocol. It follows that these can be rendered effectively unreliable or unusable by power loss during a write even if they are not damaged physically.

• If you really want, you can take an "effectively unreliable or unusable" USB memory and move (i.e. desolder and reconnect) its flash ICs to an environment that allows hard erasure. The flash ICs should be useable again now.