I avoided it from the beginning
I worked at a US university where allegedly only Eudora was compatible with their mail server for some reason. On day one I found out that Thunderbird (or was it Seamonkey at the time?) worked equally well. The bonus of the Netscape replacement was it's UTF-8 friendliness, unlike Eudora's, which was important as half the lab used in their emails non-Latin languages. So I got hated by the IP admins, loved by some coworkers and generally had fun. But I still cannot understand why some people actually liked that software.