Sanger sequencing is still used because it is well established and cheap when you are sequencing short >1000 bases and the reagent kits and equipment needed are widely available and giving better signal strength over a wider range. the analysis software is quite cheap or free.

Since the eary days of sequencing the advances that have helped to produce longer reads and better quality sequencing are better enzymes and ratios of dntps and ddntps allowing longer reads. The use of manganese instead of magnesium allows better distinction od dntp addition an ddntp addition The invention of dye labelled dyedNTPs allowed laser light reading of sequences instead of radioactive detection and the invention of capillary electrophoresis and linear acrylamide separation medium has allowed quick and easy base separation for reading sequences. The improvement of pcr enzymes and machines giving cleaner pcr product has also helped with sequencing. The development of analysis software like Phred has allowed good analysis of the base signals in the separated sequence reaction and has been fundamental in improving base reads and analysis