It is an expensive inefficiency made worse, he says, by the fact that recepients have still often had to wait for a failed delivery.

【翻译】他说，这是一个代价昂贵的低效率，由于收货人依然不得不等待失败的交付，让低效率变得更糟。

【分析】he says 理解为“插入语”。为分析方便，可去掉。

It （主语）is （系动词）an expensive inefficiency （表语）made worse by the fact that recepients have still often had to wait for a failed delivery.（过去分词短语作定语）

made worse，可以转换为定语从句：which is made worse“被弄得更糟”。

在定语部分中，that recepients have still often had to wait for a failed delivery是the fact 的同位语。

▲says Kenneth 和Kenneth says，都对。本文使用says Kenneth，主要考虑后面有一个同位语，这样处理，就是让同位语紧挨着：says Kenneth, head of business development at Postnord