At Safari's inception there were good Mac browsers. Camino and OmniWeb were capable browsers and Cocoa native. While Netscape and IE of the time sucked on Mac they weren't the only options.
I think Safari was more about guaranteeing a native browser on the Mac. There was a lot of speculation they'd adopt Camino, they hired its lead developer, but instead went with KHTML.
I'd guess they didn't want to be tied to Mozilla after watching Netscape flail around for so long. KHTML was so much lighter than Gecko as well with far less baggage to work around.
I think Safari was more about guaranteeing a native browser on the Mac. There was a lot of speculation they'd adopt Camino, they hired its lead developer, but instead went with KHTML.
I'd guess they didn't want to be tied to Mozilla after watching Netscape flail around for so long. KHTML was so much lighter than Gecko as well with far less baggage to work around.