Moral boost

[Jeeves]

As others already mentioned - This is part of the game. You can't be ready for everything.

Resources in the game are balanced so you have enough to achieve success with careful managing, but keeping your Squad fully prepared for all matches while exhausting the players with rigorous training is quite difficult - And unrealistic might I add. That is exactly why clubs (and all types of organizations for that matter) require a leader or manager. Someone has to be at the helm of the ship and steer it correctly!

Moral Boosters are an issue only when your club is performing sub-par. Just like in real life it's a closed circuit. The more your team loses the more demoralized they are and the harder it gets to turn things around, which spirals down continuously. Your players really like to shine on the pitch, so an easy way to boost your player's morale for free is to keep them away from situations that may hurt their performance. For example when using an AMC and your opponent's DMC prevents your player from reaching his potential, his form will drop and he will feel useless and lose morale after the match.

Rests are not enough mostly when Managers create too intense training drills. Sometimes you have to sacrifice the training of your team and focus the available resources on winning the match instead.
Some managers have a very easy training session that they use to keep their bonuses at 10%, without loosing much condition. It doesn't improve their players much, but they are in top-form for the match. They train to improve them when they have additional resources or when/if they drop out of the Cup/CL.

On the other hand I tend to strive for balance - Trying to train my players for quality and for Team bonuses. This way I can keep up with the competition and have enough to also get a boost during the matches.
When the later stages of the competitions hit I switch over to prioritizing Team Bonuses over player quality (A that point my players have mostly regained their former stats). Of course this depends on whether I'm still in the CL and CUP or not. :P
Otherwise it's business as usual.

[CM-16]

Sadly My Team's morale goes down hen they win. I don't know how to set their winning bonuses correctly, either...