Are there any good reasons why ternaries in C# are limited?

Fails:

object o = ((1==2) ? 1 : "test");

Succeeds:

object o;
if (1 == 2)
{
    o = 1;
}
else
{
    o = "test";
}

The error in the first statement is:

Type of conditional expression cannot be determined because there is no implicit conversion between 'int' and 'string'.

Why does there need to be though, I'm assigning those values to a variable of type object.

Edit: The example above is trivial, yes, but there are examples where this would be quite helpful:

int? subscriptionID; // comes in as a parameter

EntityParameter p1 = new EntityParameter("SubscriptionID", DbType.Int32)
{
    Value = ((subscriptionID == null) ? DBNull.Value : subscriptionID),
}