The way I heard it, Eich was hired to put Scheme in the browser, but then Sun planned a big applet event and he had a week and a half to throw together a scripting language that looked like Java, because plan B would have been something more like VBScript.
That's muddled: there was no Sun big applet event, I needed to do a demo inside Netscape to get everyone on the "it's possible to do Mocha" page.
And the VBScript threat was later, from Microsoft doing it in IE3. If I'd missed the Netscape 2 boat, it's likely VBScript would prevail (Netscape 3 was originally 2.1, and 4 was originally 3 but delayed a year; find "Collabra-driven" in https://www.jwz.org/doc/groupware.html).
