Why normalize function has a different result on a matrix vs single value?
The normalize function works by calculating z-score for the given data. Now z-score is given by:
$$z_{i} = \frac{x_{i} - mean(X)}{s.d.(X)}$$
where $X$ is your original vector/matrix.

Now, when you give a vector as input it first calculates the mean and standard deviation for the row/column. Then the output you ask for is calculated the above formula. So, if you only ask for a scalar it only shows one value. You can see in your example the normalized value(or z-score) is same for that particular position i.e. $0.24444$.

But when you give only a single value as input the z-score is 0 by definition. For more on it's working and use take a look at the docs.