Works play no part in salvation. Works come about as a result of salvation. If one does not have works, it is because they do not have salvation, not the other way around. To say that works are required for salvation, says that we are saved at least partly because of our own merit, which we know not to be true.
Romans 3:10
As it is written, There is none righteous, no, not one:
Works are a result of salvation, but that does not mean that works cannot come for some other reason as well. All dogs are mammals, not all mammals are dogs. All who are saved have works, not all who have works are saved. This is why there will be people who did pious works, yet the Lord will say He did not know them. They never had faith, only works. Likewise if works are absent, it is because salvation is absent. Not salvation is absent because works are absent. They may have believed, but even the demons believe, it is faith that they lacked.
Galatians 2:16
nevertheless knowing that a man is not justified by the works of the Law but through faith in Christ Jesus, even we have believed in Christ Jesus, so that we may be justified by faith in Christ and not by the works of the Law; since by the works of the Law no flesh will be justified.
James 2:26
For just as the body without the spirit is dead, so also faith without works is dead.