MOTM means "Man of the Match". These orange in form cards are awarded to FUT players that perform extremely well in recent real-life cup football matches.
The MOTM cards were created in FUT 12 to reward the best players of matches not covered by the TOTW cards. It is the case of the UEFA club competitions final stages, domestic cups finals and International National Teams finals. An orange card is assigned by EA Sports to the best players of these matches. They become available in packs for only 24 hours, usually at around midnight (UK time).
The ratings and attributes of MOTM cards are usually boosted in one or two points, compared with their last TOTW card or, if it doesn’t exist, their regular cards. They don’t have any periodicity. Usually they are released between March and September, because it is when the tournaments are coming to the end or when domestic Cup finals take place