A valid explanation for real wage growth is an increase in the rate of productivity.
This means that workers are producing more goods or services in a given amount of time, making the economy more efficient. As a result, employers are able to pay their workers more for their increased output. This leads to an increase in real wages, which is the amount of goods or services a worker can buy with their salary after accounting for inflation.
In other words, when workers are able to produce more, the value of their work goes up, and they are able to command higher wages. This results in real wage growth, and is a key factor in improving the standard of living for workers and the overall economy.