The complexity of the language's definition, which runs to several hundred pages filled with non-standard terminology, made compiler implementation difficult and it was said it had "no implementations and no users". This was only partly true; ALGOL 68 did find use in several niche markets, notably in the United Kingdom where it was popular on International Computers Limited (ICL) machines, and in teaching roles. Outside these fields, use was relatively limited.

Nevertheless, the contributions of ALGOL 68 to the field of computer science have been deep, wide-ranging and enduring, although many of these contributions were only publicly identified when they had reappeared in subsequently developed programming languages. Many languages were developed specifically as a response to the perceived complexity of the language, the most notable being Pascal, or were reimplementations for specific roles, like Ada.

Many languages of the 1970s trace their design specifically to ALGOL 68, selecting some features while abandoning others that were considered too complex or out-of-scope for given roles. Most modern languages trace at least some of their syntax to either C or Pascal, and thus directly or indirectly to ALGOL 68"

My guess is someone took the 'no implementations' saying as a personal challenge.