All AIs can be suicidal one way or another but some are more aggressive than others (Italy comes to mind). If you can fake intel, some AIs will not be able to determine the number/quality of your troops properly so they will attack you more / or less depending on that. If you played since start you would understand this specially when Intel / decryption / encryption was locked behind techs. All of a sudden, after completing one of those research techs, in more than 1 case, the AI would suddently stop attacking you, or start attacking you.
"Brainless" or "Suicidal" attacks aren't all that bad. In many cases, all it takes to advance a front, is breaking the (direct) frontline. And breaking it, requires breaking heavily entrenched units. If you exhaust their org, by not allowing it to recover, you can, technically, collapse a front. And continually do so (preventing new units from digging in and regaining org). This can be powerful specially when using certain doctrines and for countries with men to throw around, like USSR or China. Can also be amplified with other factors, like support companies, etc.
Even the UK does this when you invade their islands. Its not that bad, because in this case you barely have any provinces to retreat to (after invading the islands), so even the AI can be an annoyance if they break your division's org and you don't have time enough to recover it.
"Brainless" or "Suicidal" attacks aren't all that bad. In many cases, all it takes to advance a front, is breaking the (direct) frontline. And breaking it, requires breaking heavily entrenched units. If you exhaust their org, by not allowing it to recover, you can, technically, collapse a front. And continually do so (preventing new units from digging in and regaining org). This can be powerful specially when using certain doctrines and for countries with men to throw around, like USSR or China. Can also be amplified with other factors, like support companies, etc.
Even the UK does this when you invade their islands. Its not that bad, because in this case you barely have any provinces to retreat to (after invading the islands), so even the AI can be an annoyance if they break your division's org and you don't have time enough to recover it.