[laithshadeed]

I believe microservice is the wrong term used to describe SOA. The word 'micro' make it looks simple & applicable for tiny apps 10-50K SLOC. I believe you should start chopping off your monolithic app only when it reach > 100K SLOC. Still you can split it up by well defined modules with clear interface, without necessarily using SOA if it is running on same box.

Having monolithic app does not make it bad. What makes it bad is not having proper modules with proper interfaces.

SOA comes handy when you want to distribute your workload, so now we have proper modules but those modules needs more computing power, so split them up into boxes and pay the pain for managing that, because you have no option.