If you’re trying to determine your Signal Strength, you can always take a quick glance at the signal bars on your phone, which for the most part are an approximation of the signal strength you are seeing from your carrier in your area. However in Android, users can actually dive deeper into this via the Settings menu.
This shows a more or less precise reading of the signal strength denoted in dBm or asu. However in future Android builds, it seems that Google is giving Carriers the option to hide the signal strength from users. This is according to a report from XDA in which it has been suggested that future builds of Android starting with Android P could see carriers hide that option from users.
XDA notes that this is slightly different from the tweaks that carriers sometimes make to branded phones and could be applied to all phones on their network just by inserting the carrier’s SIM into the handset. As to why they are doing this is unclear, maybe they don’t want users to get confused between the numbers they see versus the signal bars on their phone, but the option is there should carriers want to take advantage of it.