The 1978 television series Battlestar Galactica is noted for its vocabulary, both of profanity (e.g. "frack!") and of measurement of time. This is an element of the show that was deliberately discarded for the 2004 re-make.
Much has been made of the way that the show measured time. John Larocque, for example, in his article, discusses the differences in usage of words such as "centon" between the pilot episode and the remainder of the series, positing that the characters in the story re-defined the words once they had become acclimated to wholly spaceborne existence.
In fact, the explanation for why the pilot episodes differed from the rest of the series is almost certainly far more prosaic, and is the one that M. Larocque touches upon at the end of his article: It's just an S.F. writers' trick, and the series' scriptwriters didn't put too much thought into it being self-consistent or wholly logical.
Indeed, you'll find that this is an S.F. writers' trick. It's one that extends as far back in Science Fiction as the days of E.E. "Doc" Smith, whose Lensman novels had invented units of currency, the "millo" and the "cento". (See Kimball Kinnison's "credits to millos"/"one cento" bet with his son, for example.) What S.F. writers want are units of currency, time, and measurement that are clearly not Earth-based, and that are believable extensions of human cultural development to a spaceborne (or multi-stellar) culture (where, of course, solar-system-derived units such as "day" or "year" are going to vary from planet to planet and star to star). There are many examples in the literature of this. It is a long-used literary device.
So put yourself in the place of a scriptwriter for Galactica. You have three motivations:
You don't want to use Earth measurements. The viewers will, rightly, ridicule your writing for being stupid. A spaceborne culture, or indeed a culture that has settled so long around other stars that it has forgotten entirely where Earth even is (the fundamental premise of the show, remember), is not going to be using Earth-based units of measurement, and even viewers who are not S.F. aficionados are going to pick up on such an anachronism/anatopism.
You don't want to alienate viewers. The vocabulary and usage must not be so far from the real world that viewers find the story incomprehensible. The approach of A Clockwork Orange is an approach best used as the exception that proves the rule, rather than the rule iself.
You don't want to spend much time and effort on this. Vocabulary of measurement (of time, distance, currency, and the like) is not a particularly major part of the show, and as a scriptwriter you don't want to spend effort on it, particulary for a pilot episode of a television series. Tidying up inconsistencies is best left for after the series proper has been given the green light, and constructing a detailed cultural back-story, explaining how the units of measurement got to be as they are, in terms of the fictional universe, is best left to the people who will do that detail work with joy, constructing things such as complete schematics of starships for books published as The official XYZ manual.
You therefore use the same time-tested literary device that S.F. writers, in particular English-language S.F. writers, before you have all done: decimalization and metrification. You create obviously systematized units of measurement, generally using the scentific prefixes for units that your viewership/readership will undoubtedly be familiar with (It is science fiction, remember.). They will be readily comprehensible to the viewership/readership, and won't become a stumbling block that impedes comprehension of the actual story. They will be a plausible extension of current human society and culture into space/the future. And they'll have that same slight degree of otherness, as well as the same positive associations with science and engineering, as the actual metric system does to Anglophone people living in countries that still haven't fully adopted the metric system across all walks of life.
Thus are begotten "centons", "millicentons", "microcentons", "cycles", "microns" (not as the real unit of measurement by that name, however), and "quatrons". And thus pilot episodes differ from the rest of the series.
One particularly interesting thing about this coinage, from a lingiustic perspective, is that it again repeats the same bastardized admixture of Latin and Classical Greek so famously criticized by Charles Prestwich Scott in the coinage of the word "television". "cent-" is a Latin prefix and "quatro-" is derived from Latin, whereas "-on" is (a romanization of) a Greek suffix, "-ον" being the neuter nominative singular suffix for the Greek second declension.
Such words, of course, are not necessarily used carefully, especially on television series where teams of writers who are primarily television series writers, rather than science fiction writers, are employed. Science fiction fans can point to examples of S.F. writer ignoramuses, who get the details glaringly wrong in science fiction because they do not have that great a (or even any) background in and understanding of science. Indeed, the classic mistake of the non-scientific writer writing out of xyr depth in science fiction is the mis-use of "light year" as a unit of time. Hence there is not necessarily consistency across a whole show, or across a television show and its novelizations or book spin-offs.
The easiest route to such consistency is to use the fictional terminology in ways that are exactly analogous to real world metaphors, usages, and aphorisms. It's simply easiest for the author to remember that way, as well as providing enough context for viewers/readers to figure out what the strange novel words are supposed to be. Doc Smith's "millos to centos" bet is analogous to the real world betting-derived idioms of "dollars to doughnuts", "nickels to nuggets", "dimes to dollars", and "dimes to cents". In Galatica, similarly, Boomer says "Wait a centon!", where in real life one would say "Wait a minute!", and Adama talks of an event taking place "in a few centars", where in real life one would say "in a few hours".