Both screen printing and DTF produce durable prints for textile surfaces. The main difference has to do with the pricing (color based pricing / print surface based pricing). In the end it all comes down to amount of colors multiplied with the surface.
Wat is screen print
Screen printing is the older of the two methods. A separate screen is created for each color in your design: a finely stretched mesh with the shape of that color gets cut out. The printer places the garment underneath and forces the ink through the mesh using a squeegee. After the colors have been applied the textile goes into a drying tunnel.
For each individual color this process gets repeated: a new screen, re-alignment, and printing. This preparation of course costs time and time is money. Printing 10 or 1000 shirts therefore is an important factor.