It's a good idea but you will run into the following issues:
* Your users won't have enough data
* Your users will have bad data
* Your users will have sensitive data that they can't upload
* Your model would need to be tweaked for best outcomes
* Your users won't have enough data
* Your users will have bad data
* Your users will have sensitive data that they can't upload
* Your model would need to be tweaked for best outcomes