This is a good question and I seek to give a good answer.
Scripture interprets scripture. It is not possible for it to contradict itself since it is the word of God.
We are saved by grace through faith,not of ourselves, it is a gift of God, not of works, lest any man should boast, Ephesians 2/8-9.
As has been pointed out above, we are not saved by faith alone. That is absolutely correct. Faith must give rise to works as is implied in the same Ephesians passage ( 2/10) that we must walk in those works.
Further James is quite clear that faith alone is dead, James 2/17, and that faith is shown by works, 2/18. He further evidences that Abraham was justified by works when he offered up Issac, v21. Faith wrought with his works and by works was faith made perfect. Abraham believed God and it was imputed to him for righteousness. God counted his faith as righteousness.
Notice Abraham believed God, not believed in God. It is not enough just to believe in God.
Thus in our parable the man failed to put his faith (talent, what God gave him in this life) to work and so lost all.
Large faith and life (five talents, Matthew 25/15) is rewarded (vvs21, 23) the same as lesser faith and life (two talents, v15) showing that it is not the amount of faith and life you have, but that you use it, that is important.
Remember that if you have faith as small as a mustard seed, which is said to be the least of all seeds, Matthew 13/32, it would be sufficient that you could say unto a sycamore tree be thou plucked up by the root and be thou planted in the sea and it should obey you, Luke 17/6. That is not to say that we do this but it is God, for faith, properly speaking, is hearing a word from God, Romans 10/17. We hear and know what God shows us He is going to do and thus we complete the circuit, so as to speak.
The life that we have now is counted as unrighteous mammon, Luke 16/9-11 and we are to exchange it by faith for the true riches, which is the life of true righteousness and holiness and of eternity. Our present state is considered to be of the least value but if we are faithful in our use of it we will "exchange" it, be entrusted with the true riches in it's place.
So is our parable. We must take what the Lord has presently entrusted to us and exchange it for the true riches, so laying up treasure in heaven, Luke 18/22.
Thus are we to be rich toward God, Luke12/21 and not be as the fool who lays up for himself in this life.
The man with the one talent buried it in the earth which is a figure of this life, not heaven, and so showed he did not have the true faith that is proved by works. That is why even what he had, this life, was taken away, and he was cast into outer darkness.
The beauty of this parable is that it appeals to all, but especially the weak and limited and not so gifted, for they can achieve the true riches and rewards equally as much as the clever and talented and gifted.
How marvellous is God's ordering of things !
We are all encouraged to strive harder in our pursuit of the kingdom of God and of God Himself.