Why do Article 120 defendants feel disadvantaged by unequal resources?

So I’m kinda stressed and hoping someone here can shed some light. A close friend in my unit is dealing with an Article 120 charge, and watching what he’s going through has me wondering why it feels like the deck is so stacked against the accused. The prosecutors seem to have a whole army of investigators and experts, while the defense looks like it’s just scrambling to keep up. Is this normal? Is there something we’re missing? I just wanna understand what’s going on and how people get through this mess. Any insight would really help.