Why don't Armies(with overwhelming numbers)flow in continuous troops at a breach)?

Question

I watched the Peter Jackson Lord of the Rings Trilogy this week. I notice during the sieges once a breach like the blown wall in Helm's Deep or the battered gates in Minas Tirith was created, the Orcs simply send in hordes and hordes of unlimited troops into the breach continuously until they overwhelm this enemy.

As in the entire army quickly tries to run into the breached area nonstop no matter how many are killed. There is no sense of organization of "Send X Unit" and then "Send X Unit later" and such. Basically like the gamed human waves of the Chinese in the Korean War, they simply keep sending their Orcs into the breach until even when whole units are getting killed until they overwhelm the defenders. The only time they stop and organize in the Siege is when they reach another obstacle like another strong gate or a separate city wall as seen as they are ramming the final gate of Helm's Deep or as seen throughout the various parts of the Siege of Minas Tirith in which they literally temporarily stop as they take each layer of the city so they could bring in a ram and attempt to break the gate of the next wall.

However I also watched the Bakshi Lord of the Rings adaptation. In This version, the Orcs besieged Helm's Deep at a better organized manner. Yes they sent in a large force to swarm in the breached walls in the Siege. But when Theoden did a counter attack at the end of the movie, the Rohirrim though they were winning the Siege at least because their counter cavalry charge was so aggressive the Orcs were literally retreating from the ground they took in the fortress and were getting hacked to pieces.........

Until when Theoden finally chased went outside Helm's Deeps perimeter he finally saw the force thats been attacking Helm's Deep was only a small fraction of Saruman's army and outside the castle walls stood another organized group of Orcs that was waiting throughout the siege for either the initial wave of Orcs to take over the castle or get repulsed. This force basically was going to attack and finish off what was left of the fortress had the initial Orcish wave failed. And they were a CONSIDERABLE distance from the Fortress and were organized in mass formation standing their like waiting for their turn.The number of Orcs awaiting outsid eof Helm's Deep were so much Theoden's cavalry charged stopped int ehir tracks out of sheer demoralization and shock that there will still many Orcs outside the fortress and they would have been routed if Gandalf did not come with reinforcements.

Were as the Jackson trilogy portrayed the Uruk-hais as sending in non-stop flow of troops into Helm's Deep once it was breached and basically disregarding and formation once they got into a castle. Basically a disorganized barbarian style attack in the Jackson Trilogy after breaching the wall as opposed to the Bakshi movie where they literally were organized into at least two separate sections groups to be used at various intervals of the siege.

Now I notice so many movies LONG BEFORE the Jackson Trilogy was made pretty much portrayed sieges in the same manner as Jackson's movie did. With the exception of when they are ramming down castle gates or when there is another wall within the castle to breach, movies before Jackson's adaptations who that once the gates or a section of the walls were breached, the rest of the siege proceeded in the same manner as Jackson's LOTR where they send in hordes and hordes of seemingly unlimited troops to attack into that breach nonstop until that section has been overwhelmed by the besiegers. Basically win through sheer numbers and disregard almost any formation and tactics minus bombarding with artillery and ramming castle walls.

However I read in real life most sieges resembled the Bakshi version of Helm's Deep where on section of the besieger's forces get sent in and even if the besiegers outnumber the defenders by a ratio of say 50 to 1 or even 100 to one, the Besiegers remain organized in formations in their attacks and use different groups throughout the sieges to enter the fortress's breach at various interval to reinforce troops currently fighting int he castle or to continue the attack if the initial group sent into the breach was wiped out.

I very rarely read about the Besiegers hurling in their entire force to enter a breach like they're canon fodder and even at the final intervals of the siege, the besiegers often attack still in an organized manner using different units for different stages of the final days of the siege.

Answer 1

1. We are humans not orcs.

2. Movies often do not reflect reality.

3. Logistically it is not easy to flow an entire army through a breach.

4. With the right tactics it is actually very easy for a small force to defend a bottleneck, so getting through is not as easy as it might seem. Ever hear of the Battle of Thermopylae or the Battle of Stirling Bridge

Answer 2

If you jam your army into the breach, you end up with a mostly dead army whose bodies you must get over to continue into the breach. The besiegers are basically sitting ducks. What the breach does do for them is draw defenders away from other points in the defenses and makes it possible to create a second or third breach or use siege ladders and siege towers to enter the fortifications.

If you're going to attack a breach do it in the dark with a limited force and stealth.

Answer 3

Basically, Peter Jackson was making a homage to those older films, like many films do (repeating the same trope or even scene in honor of the previous ones), and because viewers have become used to expecting such scenes (which is largely why film remains at 24 frames per second when our phones have cameras that can take film at a much higher frame rate - we are used to seeing film at 24 fps and view anything higher as looking "cheap").

Answer 4

Human wave attacks are costly and usually do not work as well as coordinated attacks with with a reserve to be used to finish the deal (or cover the retreat). They didn't work on the Western Front in WW I (in which Tolkien had fought and had intimate knowledge), at the Chosen Reservoir (the Americans were still able to fight the Chinese off and escape the trap) or during the Iraq/Iran War (Iran never broke the Iraqi troops and invaded Iraq).