Right. A recurring theme in successful military campaigns (though by no means enough to ensure success) is a very clear objective. Civilian politicians decide those objectives. If the objectives are vague that's
their fault. If the objectives are unachievable, that's
their fault. Only when there were clear, achievable objectives is there any opportunity for it to matter whether military leadership, tactics, training, equipment etc. were adequate.
After all, if we don't know what success even looks like, what chance do we have?
Compare "Corporate" (the British operation to re-take control of the Falkland Islands) with "Iraqi Freedom" (US invading Iraq for nebulous reasons)
Even if you're not sure that Corporate was a good idea, or that the UK "should" own these islands, the objective was very simple and easy to understand. If we kill a whole bunch of Argentinians but have to retreat and they keep the islands, that's a failure. If they just walk away without a (further) shot fired and we get the islands back, that's a success. Easy.
But what chance did US troops have for "Iraqi Freedom" ? Can they find the imaginary Weapons Of Mass Destruction in Iraq? No. Hopeless.