These battles have hidden messages- If you violate the commandments of shariah, Allah swt won't tolerate it.

Uhud:

Some of the Hazrat Sahaba Ikram rz.a used their reasoning power against the commandment of RasulAllah sallallahu alaihi wasallam. What happened- is a historical fact.

It's another massage that we must never believe in rumours as Hz Sahaba Ikram rz.a begin to fight to die when they heard of RasulAllah sallallahu alaihi wasallam's death.

Hunain:

Muslims can't win and succeed against Kuffar in any field unless they've support of Allah swt. Some of the new Hz Sahaba ikram rz.a felt a bit of confidence over their number of soldiers against enemies. Allah swt doesn't like anything which goes against His Majestic rules and laws.Only 200 enemies had turned the tables.

Mo'tah:

Discord and chaos was prevalent in Medina when hypocrites and other new Muslims who misjudged the situation and denied to pay Zakat. Hz Abu Bakar Siddiq rz.a, the khalifa- despite all the adverse aura and suggestions of Hz Sahaba ikram rz.a not to send the army to the battle field, He rz.a followed the decision of RasulAllah sallallahu alaihi wasallam.What happened is known to us.

Allah swt knows best.