The Internet, originally designed for U. S. government use, offered only one service level: Best Effort.
No guarantees of transit time or delivery
Rudimentary prioritization was available, but it was rarely used.
Commercialization began in early 1990’s
Private (intranet) networks using Internet technology appeared.
Commercial users began paying directly for Internet use.
Commerce sites tried to attract customers by using graphics.
Industry used the Internet and intranets for internal, shared communications that combined previously-separate, specialized networks -- each with its own specific technical requirements.
New technologies (voice over the Internet, etc.) appeared, designed to capitalize on inexpensive Internet technologies.