Forbes Magazine says this signals defensiveness!
“Arms can act as the doorway to the body and the self. When they are crossed, they form a closed defensive shield, blocking out the outside world. Shields act in two ways: one is to block incoming attacks and the other is a place behind which the person can hide and perhaps not be noticed.
“Crossed arms may thus indicate anxiety which is either driven by a lack of trust in the other person or an internal discomfort and sense of vulnerability (that may, for example, be rooted in childhood trauma).
“The extent of crossing indicates how firmly closed the person is. This may range from a light cross to arms folded to arms wrapped around the person. An extreme version which may indicate additional hostility is a tight close with hands formed as fists. – SOURCE: Changing Minds.org
“When you fold your arms your credibility is substantially reduced.” – West Side Toastmasters