I've never experienced them breaking that quickly, but it's worth pointing out that the cheap models are far inferior. The motors are weaker and they even come with a worse charger that doesn't come with a normal wall outlet plug.

I don't like USB-C for toothbrushes to charge because there's water in the bathroom. The proprietary inductive charger/stand that comes with Sonicare/Oral-B electric toothbrushes are ideal.

Sucks that they are proprietary but they have been trivially easy to clone by third party manufacturers. $7 on Amazon.