An up-to-date supplier price list is useless if a price gets mistyped as it goes into the system: a digit transposed, a decimal missed, a line skipped. These are small errors that, multiplied across dozens of materials, quietly distort the cost of every quote that uses them.
The risk in typing it out
The longer a price list, the higher the statistical probability of a transcription error. It is not a question of concentration: it is arithmetic. A 200-line price list keyed in by hand will, by simple probability, contain some wrong lines — usually spotted months later, when a margin comes out oddly low.
Importing from a file moves the check upstream
Loading a price list straight from the supplier's spreadsheet, in an agreed standard format, moves quality control upstream: you check the file once instead of every line by hand. The time saved is not only the typing, but above all the time you would otherwise spend hunting the error months later.
Update on a schedule, not when you remember
A price list imported once and never refreshed is still a risk: material prices move, and a list a year old produces quotes calculated on costs that no longer exist. Setting a regular cadence — even just quarterly for your main suppliers — keeps the benefit of automation alive over time.