In simple words: EfficientNet is a CNN family designed around efficient scaling.
Three dimensions
CNNs can be made deeper with more layers, wider with more channels, or fed larger images. EfficientNet scales these dimensions together in a planned way rather than increasing just one.
Why balance matters
The goal is good accuracy for the available computing budget. A larger model can cost more memory and time; the right choice depends on the device and task.
See the flow
depth + width + image size→balanced scaling
Simple example
A mobile image app may need a smaller efficient model even when a larger model scores slightly better in a lab.
Remember: EfficientNet is a CNN family designed around efficient scaling.