By duplicating and sharing the data, it cannot be manipulated or controlled by any one person or thing. Each block contains data in its current form. Data can only be changed when and only when the validation criteria is met.
Imagine your the car title as blockchain technology data and duplicated several thousand times. Most people own their vehicle for several years. The car title data is sitting there. Updated every 10 minutes for as long as you own your car. The title data is safe. You would have to change several thousand duplicates in order compromise the data. Validation points and encryption protect it. One day you sell your car to a new owner. The system recognizes you as part of the validation process (a node). A new blockchain is added. The new owner is now part of that validation process (a node).