Transactions are extremely simple for miners to process and they can be processed nearly instantly.  The problem is that improvements in miner technology along with dramatically increased revenue from the rising price mean that there dramatically more miners than are actually needed to secure the network.  Furthermore, to scale the network miners have to come to a consensus on what to do, and by not scaling the network miners earn the transaction fees on top of the existing block reward, meaning that there are more and more miners added which seldom actually want to scale, and if they do it's only out of the desperate prospect that Bitcoin might become less popular.

Therefore the network will scale once everyone rushes to do everything at the same time with no actual consensus, or once BITMAIN and other monopolies give up on BU to shift to SegWit.

Eventually, I think it does have to happen.  Naturally, if people ran away from Bitcoin to alts (not actually happening yet) a scaling solution would be implemented.