The merge node sometimes gives:
[
{
success:true
}
]
This is unexpected as it should give the merged result, this causes the further nodes to malfunction. Upon re-running the node, it works fine.
Also, sometimes the node runs before all of its inputs are available
Refer the image attached.
You can clearly see that the node marked with blue is still executing but, the merge node (in red) has produced its result (in yellow).