Why bother with the size increase.
- In Mighty Morphin Power Rangers
- The reason Rita didn't leave the monster small is because they'd eventually use the Power Blaster on it which would finish it off even more effectively than the Zords in most cases. For example, the Spit Flower overwhelmed the Dragonzord Battle Mode, but later reappeared small and was beaten by the Power Blaster. When the Rangers attempted to use the Power Blaster on Slippery Shark, Rita got worried and threw the wand to make the shark grow, causing the Power Blaster attack to miss. And in a case where both defeated a monster, the Power Blaster defeated Gnarly Gnome as did the Megazord. This also happened in season 2 with the Thunderzords when the Power Blaster would continue to defeat enemies, only becoming useless late in season 2.
- In Zyuranger, Bandora, Rita's counterpart was too weak to throw the wand to make Dora Circe grow and it got destroyed by the Howling Cannon. Bandora made Circe grow to prevent him from being destroyed, only to have the rangers call their Mecha.
Why they do not start Big
- MMPR
- Lord Zedd often grew the monster immediately, but it seldom helped. On the sentai side, the Gokaiger monsters accused of cheating for doing this also lost anyway, though sometimes it's because the plan wasn't your usual smash and bash. Also, look at the giant in the second ever episode. He was killed by the Tyrannosaurus ground breath attack, the weakest zord finisher on the show. Turbo Megazord was captured not by a monster, by by the villain's Humongous Mecha.
Why the heroes don't use their mecha to crush the monster when its small
- In MMPR
- One of Zordon's rules is that the rangers were forbidden to escalate a battle without being forced to, and breaking that rule would result in "losing the protection of the power". Given Zord's high standing in the verse, it's likely the other Big Goods follow this rule as well.
- Despite this rule, the rangers did summon the Zords when the monster was still small but only if they were getting beaten really badly. For example, when Green Ranger was stomping the 4 rangers (Jason was absent) they did call Megazord (despite lacking one member) out of desperation. He rather stupidly tried to attack it anyway but was quickly frightened away. (This was different in Zyuranger where Burai had used his new sword to defeat everyone. Daizyujin activated on its own to save them.) There was a another instance against the first of Zedd's monsters the Rangers called the Zords right away after he fired an opening shot at him (presumably because they'd been warned just how strong he was) but this was a bad idea since the monster froze the smaller ones, and gained control of the bigger ones.
- Beetleborgs gave the following justification: summoning the Humongous Mecha against human-sized monsters in the middle of the city can do more damage than they were preventing. Tomica Hero Rescue Fire also brings this up in one episode.
- GoGo Sentai Boukenger had a memorable instance when Bouken Yellow, having used the giant robot to perform another task, comes by to help the others fight a swarm of mooks while still in the robot, forcing the remaining Boukengers to dodge the robot's attacks. Yes, Yellow's The Ditz, why do you ask?
- In Tokumei Sentai Go Busters, the villains send Humongous Mecha to back up a normal-sized monster. The mecha are actually mass produced, but are given some of the monster's thematic design elements before they're sent out. This is a Justified Trope in the sense that the Mech and the Busters perform two very specific roles. While the Megazord could easily overpower the smaller Busters or Monsterofthe Week, they consume a veritable supply of Enetron which means that at best, they are horribly inefficient for the task and at worst, utterly useless. This is compounded by the ridiculous amount of work needed to maintain them, meaning that the odd monster is not really worth bringing out a giant robot that cannot enter buildings. The Megazords running out of power is also a major plot point on several occasions which means that unless they are strictly necessary, they should not be fielded.
