My recollection is that VB6 deployment got messy when you started stringing together lots of third-party components, since they had to be installed and registered system-wide. Windows XP introduced registration-free COM through SxS manifests, but a lot of us couldn't use that for years after XP came out, because we had to keep supporting 9x and maybe 2000.
Yeah, once data files, OCX controls and more got involved you had to build an installer and Microsoft didn't provide any solutions for that until MSI came along. And InstallShield was expensive. So that hurt VB just as people were moving towards the web where you didn't have any dependency issues like that (assuming all the servers were online).
