Reason(s)
1. Mr. Okuda, for the most part it appears, didn't contact the VFX houses-IL&M, for example-for information on ships. He obtained the information second hand. This is demonstrated by his ignorance of the USS Valiant NCC-20000, or the other ships produced by the VFX various houses. And, when in doubt, he didn't contact these houses for verification of facts. Two examples-the registries of the USS Saratoga and the USS Farrugut.

2. Mr. Okuda is very busy and appears to not keep complete records of both the modeling and the computer displays in his archive for future reference. How else to explain the issue with the USS Cochrane (which was known to the TNG Companion's author) or the registry of the USS Raman? Remember, in the days of TNG, the modeling of ships was done either with his supervision or with the supervision of an associate of his.

3. The reader doesn't have verification of many of these registries. We are told that these registries are in okudagrams, and that many of those okudagrams may not be available. They could have been deleted or misplace or locked in a file. (How does one lock computer files, so that they are not accessible later?) If Mr. Okuda is going by memory as is evident in some cases, then he could be producing mistakes and, as a reader, we wouldn't know these mistakes for we can't verify the sources. This puts a majority of the registries in doubt.

"I need to feel that I am enjoying the show, and not worrying wheter this ship has the proper registry, the name spelled accurately, or is technologically appropriate for the time frame she is operating."