Floor heating is not as warm as I was expected
Floor heating systems are very slow and normally meant to run 24/7 except for long-term absence (> 3 days), if the building hull is insulated to some extent or if it is a huge building with high volume-to-surface ratio.

Do the neighbours have the same problem? Which floor is it?
How many outside walls does this flat have? What is below the floor, what is above the ceiling?
Any valves besides thermostats in the flat?

The warm pads could be caused by domestic hot water (circulation) lines.   

Reasons for underperforming:


In new buildings, much energy is needed to dry the walls, floors and ceilings. 
In older systems, clogging could be the problem since the tube material (plastic) allowed for oxygen and other gases to diffuse into the system increasing corrosion at the metal parts. Also bypass valves can be blocked (not closing ⟶ more or less heating water is bypassing the room) by tiny rust parts.
There could be valves for each room (in this case for each apartment), near the heating system or somewhere hidden, which are meant to adjust the throughput which might be different e.g. due to unequal tube/hose loop lengths. These valves are different from thermostat valves and could be de-adjusted.
Incorrect settings or design of the heating system, or not enough maintenance, especially with heat pumps. Heating water temperature too low, pump power too low, incorrect location for outside temperature sensor (on sunny south side instead of north), restrictions by timers etc.