The progressive development of law would thus be diverted from its normal course by a legal rule laying down in advance a practice that would give rise to custom, regardless of what States actually did in that regard.
假若一项法律规则不顾各国在这方面的实际做法，事先规定一种会产生惯例的做法，那么，法律的逐渐发展就会因此而偏离正常轨道。