Deleting rows from glide table

On a screen, I have a counter for total rows & a delete button. I am testing deleting all sample data rows approx 3000. Each row has approx 30 basic columns so its not a huge table.

At the first click of the button, the number of remaining rows changed to 0 immediately.

(I knew this was not right, so I closed the app and opened again and the number went back up quickly to near 3000)

the delete is very slow, I would assume since its a glide table it would be way faster. the counter is going down only a few rows a time, this is going to take more than a few minutes.

any suggestions or advice on deleting, is deleting rows via API faster or more secure?