Just because Lionel Messi didn't play in Milan, it doesn't mean he didn't want to. This is backed up by the fact he made the trip over there and was only removed from the squad list at the last minute as to not take any unnecessary risks. It was the decision the coaching staff took and it was also the one recommended by the medical team. However when we're talking about Messi, it's the footballer himself who has the final say. He knows his body better than anybody else. After listening to those closest to him, Messi decided it would be best not to feature against Inter.
Next Sunday, the 11th November, it'll be three weeks since he broke his arm in the match against Sevilla. The medical team stated that Messi would need three weeks rest before being able to return to action. However with the calender offering up the fixture against Betis, which is followed by a 13-day break due to international football, it might be wise to take the extra time. The next match after that is away to Atletico Madrid - a match Leo cannot miss.
At the moment it's unknown whether Messi will be involved in the game against Betis. Leo is mature enough to know when he's really ready so the decision will be entirely his. The little Argentine is desperate not to miss any more playing time and even turned up to the training ground today in order to train alone. Messi will wait until the last minute to decide whether it's worth the risk against Betis or have an extended rest so that he's 100% for the important game away to Atletico.