Defending properly doesn't always mean getting the highest absorb and avoid getting breached: there are strategies that let you protect your attackers and economy without relying on those principles. This page lists some of those strategies.
'Breach me if you dare'[]
'Breach me if you dare' is an emote referring to a situation where one player willingly lets their opponent the possibility of wiping out their defense, or even breaching them, because they assume they can gain an advantage from it. This gambit makes sense when the player allowing the breach only does so for a small amount, typically less than the Health amount of their main attackers, and/or when their opponent would have to invest a lot to get the breach (for instance using a lot of Frostbites). The point of this bet is either to lure your opponent into making a mistake, or simply to free resources by defending for less.
Breachproof[]
This strategy forgoes the use of Absorb by taking advantage of the large amounts of health of Green units. The principle is to get ahead of your opponent economically, and start massing Green attackers such as Iso Kronuses, Venge Cannons or Gauss Cannons, while possibly being backed by Trinity Drones or Thorium Dynamos to protect your economy. Since you won't be buying Blockers at all (or few of them) your opponent will able to breach you every turn, but the damage they inflict will be minimal due to all of your units being hard to kill. A player attempting to go breachproof typically won't invest in a Blastforge at any point in the game (unless units like Militia and Ebb Turbine are present). That strategy is most useful when there are no good defenders present or the sets chill makes defending hard.
Full Frontline[]
As a rule, units with Frontline have more health per gold cost than their backline counterparts. They also never have fragile, meaning that they can only be destroyed in one attack. This presents a strategy when multiple units with Frontline are present in the random set, typically Wild Drone and either Iceblade Golem or Shredder: since the weakness of Frontline units is that they cannot be blocked for, rushing frontline units forgoes the need to block, similar to the 'breach me I don't care' strategy. If your opponent cannot muster enough attack to deal with them in time, the early pressure can take the game.