Currently it takes 1-3 hours for a transaction to complete if we do it with less fee? Is it possible in future that this transaction time will reduce or may be even become instant? Like when all Bitcoins are mined and there are mainly holders instead of traders and volume of transactions decline.
With the way the consensus operates now, it takes 10 minutes or less for the next block to be mined into the blockchain. After all bitcoin has been mined, I am not thinking the volume of transaction will decline because of how I have envisage bitcoin adoption to be by that time. If more people now hold bitcoin, we won’t have decline in transaction volume and more people will be transacting from time to time as we are experiencing now which will give the miners more competitive advantage when bitcoin owners set the transaction fee for their transaction to be processed faster. There won’t be decline in transaction fee and the time can also be reduced but not below an average time of five minutes.
Confirmation of Bitcoin transaction depends on the transaction fee you pay to process the transaction.
Most times, using CEX to send bitcoin transactions might be delaying because they have a fixed transaction fee which is estimated based on the network congestion, therefore, you have no right to speed up the transaction in case if the network get congested along the line. But using non custodial open source wallets that allow you to customize you transaction, you can run your transaction within 10 minutes or in less than 10minutes depending on the fee you used.
Centralized platforms add more than one transactions together and set a transaction fee to disburse them all. If they set high transaction fees for transactions, it could be bad market for them, so they set it to a price that will be profitable for them after the transaction has been processed. Maybe in the future, centralized platforms may allow users to set transaction fees for themselves but the disadvantage of it will be when users mistakenly set high transaction fees for small transactions as it is already happening to some people using decentralized platforms.
For instant transcription to happen in seconds or less than 5 minutes I don’t know if it is possible, but I will await response from other bitcoin experts to shade more light on that.
I have not come across a transaction that took place in less than five minutes before, they mostly happen within the time range of 8-10 minutes. Difficulty is increased when a miner mines a new block faster than the 10 minutes set averagely for mining a block into the blockchain. Thus, the next block to be mined will become harder than the previous one that was mined in less than 10 minutes. If the new one takes more than 10 minutes the difficulty will be reduced for the next block to be mined. That is how the whole process continues.