The WI-FI connection speed doesn’t correspond to the contracted.
The actual WI-FI speed depends on features and settings the equipment used for the connection, number of clients connected to the network, bandwidth hogs, and other wireless networks and radio-frequecy interferences in the same range.
The matter is that the wireless access point can maintain a constant connection only with one client at the same time. The WAP usually operates in a so-called half-duplex mode, enabling only two-way connection.
If there are two users connected to the Wi-Fi network, the WAP will deliver signals in turns, switching between two channels. Respectively, the real speed will be twice lower than the maximum actual speed for one client.
Depending on how remote the client from the WAP is and how many hogs and radio-frequency interference are in the range, the potential and, as a result, actual speed rate will vary.