Hi Alejandro
It really depends on the underlay network topology. From the source of your pings towards your destination, you first need to identify which device is dropping either an ICMP request or an ICMP reply. You could start doing some pings from intermediate devices until you find one that doesn't miss any of them. After that, you can start doing some packet captures at inbound and outbound direction on the offender device.
A ping loss can be caused by a lot of reasons, processed switched packets limited by control plane policing, hardware rate-limiters, firewall policies, output drops as a result of exceeded buffer utilization in one link, etc. The important part is to figure out where is this drop taking place.
