Both the SEO and SEM keep importance at their own.
SEO is just like u need to learn google algorithm and your business needs min 2-3 months to be promoted. But the important thing is once your business got prompted it will go long through SEO, U will get leads for long time,and important thing is you can do this without any cost..but the drawbacks are like it's too much difficult to compete your competitors.
But as per SEM is concerned you can promote your business in a day only, you can compete with your competitors easily. But it is totally DEPEND on how much money you are spending, so you have to spend Money in SEM.
SO ,It is depends on your business, if it is like wise to quickly promote and you have money than go for SEM for example you are garments seller and you want to online marketing for Diwali sale and Diwali is just after 10 days,than you must go for SEM..
AND if your business have enough time to be promoted and their is some Money issue you should go for SEO.
BUT if it is talking about the market scope, then no doubt you must go for SEM ,Because all the MNCs and institutes and all are mostly preferred SEM because they need instant sales
