Yes it does get better at detecting seizures the more it "learns" from false alarms.
Check out empatica dot com for questions about the details of what the watch does. They have a great Q&A section.
I do recommend one. The peace of mind it's given my husband has been worth every penny.
Does require a "perscription" request from your doctor. Totaly worth it.

"Things like brushing your teeth can set it off."

I find this quite annoying as brushing your teeth is not an activity which is going to take your heartbeat out to the roof.....Must be a lot of false alarms, thus create a lot of stress for nothing. When the idea is to reduce the stress and better deal with seizures when they happen.
I just find it incredible that in 2024, with all the tech we have there seems to be no device that does a reliable job of detecting and sending alerts.

No enough of a market ?
Margin would be too small to invest ??
Fear of being sued if something goes wrong such as a dramatic seizure not detected ???

That would figure...I just asked a question about this and didn't get the question that you had asked. DUH!
Yeah... They don't alert you're going to have one but alert others you ARE having one.
I got mixed signals about wearing it on the dominant it non-dominant wrist. Things like brushing your teeth can set it off.

Does it get better at picking up the actual seizures after learning when you tap not a seizure?also does it alart you if your heartbeat suddenly jumps up ect?

I've had mine 6 months. There has been lots of trial and error. Example: Vacuuming the floor set off the watch. But after each time it detects "a seizure" it asks: Was this a seizure?