Why is it so tempting to chase new signups while your current users slowly drift away?

I used to think low growth just meant my marketing wasn't loud enough. Every week was a scramble for fresh traffic while people who signed up a month ago were quietly slipping out the back door.

It wasn't until I actually reached out to a few active users to ask why they almost quit that I realized how many tiny, stupid bugs were driving them crazy things I could have fixed in an afternoon. Pouring money into ads feels productive but it's totally useless if the house is leaking.

Do you track why people leave or do you mostly focus on getting new ones in?