Why describes the transmission distance “Outdoor 300m, Indoor 100m”, but actually it’s hard to achieve?

Theoretically, the wireless router transmission distance is between 100 - 300m according to the IEEE802.11 standard. The transmission range is affected by the following factors:

-Wall material and thickness: Under normal circumstances, go through a load bearing wall, the signal attenuation is large;

-Wireless Transmit Power: The stronger the wireless transmit power of the router, the greater the signal strength;

-Antenna gain: The greater the gain, the stronger the signal strength;

-Working frequency band: The current WiFi has 2.4G and 5G two bands, 2.4G signal is better than the 5G’s on the penetration ability in the same environment;

-Antenna angle: Under normal circumstances, the angle of the omnidirectional antenna in the room can be placed vertically to achieve the best results.