Why c# decimals can't be initialized without the M suffix?

Question

public class MyClass
{
    public const Decimal CONSTANT = 0.50; // ERROR CS0664   
}

produces this error:

error CS0664: Lit

Answer 1

The first example is a double literal. The second example is an integer literal.

I guess it's not possible to convert double to decimal without possible loss of precision, but it is ok with an integer. So they allow implicit conversion with an integer.