Six in the fourth place answers a familiar situation: the querent occupies a middle role, with someone genuinely capable working below or beside them and someone with authority above. The reading is unusually open, since nothing at this position is said to be disadvantageous, but the openness is conditional on a single behaviour. The querent is to keep diminishing their own claim, actively and repeatedly, rather than settling at whatever level of modesty they have already reached.
What makes the line practical is that it names no reward. There is no promise of promotion, credit or good fortune here, only the assurance that nothing will go badly. A reading landing on this line often concerns a period of service or support work, and the honest counsel is that the value of the period lies in what it protects rather than in what it gains. Attempting to convert the position into advancement is the one move the line implicitly rules out.
The two failures available at this station are worth naming, because a querent can usually recognise which one tempts them. One is quietly absorbing the credit belonging to a more capable colleague. The other is filling space that properly belongs to whoever holds authority. Deepened humility answers both at once, which is why the text gives one instruction rather than two, and why it can then say that nothing done from that footing will turn out badly.