The ThinkPad T450 has an SSD storage medium which is better than the HDD storage medium found on most medium processor core notebook PCs that have been around for a comparable time to it. Solid State Drives (SSD) store data in semiconductors on a circuit board rather than using magnetic or optical media. Solid State Drives have no moving parts which makes them very fast and reliable.
This notebook PC's storage medium (SSD) is actually the best storage medium across all comparable spec laptops that have been available for more than a year.
The worst storage medium across similar types of notebook PC is HDD.
If you would prefer a laptop with a better storage medium then you might also want to look at the Elitebook 820 G2[pl_2886802_price] (SSD), or the EliteBook 820 G2[pl_2897415_price] (SSD) both from HP.