People often think wrongly about how is rushing and how it affects gameplay. Arguments against rushing is usually weak and unsupported, but rushing has very clear cut and obvious advantages. Here’s some misconceptions about rushers:
1) Your weak defenses are going to get smashed
Counter: No matter how maxed you are in TH8, you cannot stop a TH9 attack, only bad TH9s. No matter how maxed you were in TH8, as a new TH9, you’ll be smashed regardless. Another point is, strong bases attract strong attackers, weak bases attract relatively weaker attackers.
Defenses are a futile effort:
2) You’ll progress slower by rushing
Counter: As long as you keep all builders busy all the time, you’re going to reach maxed regardless of time. But a maxer would stay in TH8 for a longer time, have idle builders; while the rusher will not have this problem provided you farm enough
3) Since it takes the exact same amount of time to upgrade, you gain no time by rushing
Counter: A maxer will stay in TH8 for longer time and eventually have idle builders while working on lab. The maxer is also more likely to have idle builders towards the end of TH9
4) Loot penalty
Counter: If you’re farming correctly, TH9 gains more loot per hour than TH8 and TH10 gains more loot per hour than TH9. Only TH11 so far suffers from any form of loot penalty
5) Weak in wars
Counter: Doing it correctly, you’ll always perform better in wars. You, as a rusher, will meet with premmie TH9s or maxed TH8s. Both easy enough to demolish. A properly rushed TH9 can hit way up and take out a maxed TH9 with almost the same ease of a maxed TH9
6) A rusher needs to catch up, a maxer does not
Counter: Yes, a maxer will be in a better spot on day one of TH9. But by the time that has happened, a rusher would have been a 2-3 month old TH9. So who is better? New TH9 with 200 camp spaces, TH8 maxed troops, 10/0 royals, maxed skulls; or a rushed TH9 with 220 spaces, lvl 6 farming troops and TH9 war troops, 15/15 royals, half legos.
Now, the maxer has to catch up to loss progress
This is my guide written almost half a year ago which still holds true: