Unreachable code detected in simple method with only one return

I know there’s a bunch of related questions but I only have one line returning from this method and can’t see why the return line would be unreachable:

public List<int> GetMiddleLaneForAI(Room r)
{
    int laneCount = GetLaneCount(true);
    List<int> matches = new List<int>();

    for(int x = 0; 0 < 5; x++)
    {
        if(aiCardFrames[x].deployedCard == null)
        {
            if (laneCount < 3)
            {
                matches.Add(x);
            } else
            {
                if (x > 0 && x < 4)
                {
                    if (aiCardFrames[x - 1] != null && aiCardFrames[x - 1] != null) matches.Add(x);
                }
            }
        }
    }
    return matches.Count > 0 ? matches : null; // unreachable code detected
}

>Solution :

Look closely at this line:

for(int x = 0; 0 < 5; x++)

When does this for loop exit? 😉