The other most often repeated theory of the derivation is that it is a mispronunciation of 'box standard', the term referring to unmodified goods coming straight from the box. This appears to be a later expression, first recorded in 1983, but is likely to have been around in everyday speech for some years prior to that. If one phrase did influence the other, it is more likely that 'box-standard' is a mispronounced or euphemistic version of 'bog standard'.
There's a lot of fake etymology out there, no more than urban myth. Then people who don't understand that basic fact of modern life get all precious over one theory that they credulously accepted as gospel.
And the supposed Meccano origin for ‘Bog Standard’ and ‘Dog’s Bollocks’ is almost certainly that. There’s no evidence to support it, it’s just a fun story that has taken hold.
[citation needed]
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