>Laying off randomly and not low performers
Low performers? By what metric? And your metric sucks, that's because a single metric is meaningless, even 10 metrics are useless.
Did you do over 200 CLs a year? 10000 LoC? 10-20 design docs? 10 product launches? CL comments, reviews, bug fixed, filed?
Sure you can identify outliers, but the baseline is not exactly very telling.
In my other companies layoffs were always random.