The reason why your 2 year old throws himself on the floor is due to frustration or an inability to communicate his needs.
A 2 year old throwing himself on the floor is a common behavior and is also known as a temper tantrum and every 2 year old or toddlers go through tantrums.
Tantrums and throwing themselves on the floor are a normal part of the toddlers or 2 year olds development as they learn to express their emotions and manage their feelings.
Toddlers are not able to express their feelings or what they want like older kids and teens and adults so they get frustrated, which also leads to physical expressions such as throwing themselves down on the floor.
Toddlers and 2 year olds are also still developing their ability to regulate their emotions, which makes them more prone to outbursts, when they feel upset or overwhelmed.
Sometimes toddlers also learn that throwing themselves on the floor gets a reaction from their parents or caregivers, even if the reaction is negative and they may throw themselves on the floor and have tantrums to get attention.
Toddlers and 2 year olds will also throw themselves on the floor and have tantrums when they are tired or over tired or overstimulated.
Tantrums are very common in toddlers between the ages of 18 months and 3 years as they strive for their independence and test boundaries.