Since the beginning of this year bitcoin transaction time is too long...
We have to wait for the hours to get the bitcoin..
What is the reason behind it ?
Does anyone know it?

I don't know if you are just a trolling or you just haven't tried to make any Bitcoin transactions in this past few months. Try to make a transaction today and set it low transaction fee, it will not take an hour before it gets confirmed, maybe just a few minutes it will get thru because there are only 1763 of unconfirmed transactions (at the time of the post) today so it will be more faster and cheaper to make transaction right now, check here https://blockchain.info/unconfirmed-transactions if you want try to set the fees to priority, then it will be almost instant and hey it is not expensive like it was before.

Are you sure you are using Bitcoin? Cause the Bitcoin that I have been using for transactions has been very fast for the last two months. And the fees is also at the lowest point for the past year. Also with segwit released it should speed up your transaction speed even more if you use it.

Its takes to much time for safety transaction purposes to protect our accounts  from the scammers or hackers for me its not a big deal as long our transaction process is protected

Seriously from where you get this information about starting a thread like this, have you done a bitcoin transaction in your life and do you really know the transaction fees and the time it takes now.  
The issue you were talking about is in the past and those issues are sorted out by making changes in the transaction format.

Seriously , do you really know what you are talking about.

Because BTC need more time to confirm transaction
And if have more than transaction mean more than time to confirm