For areas with short growing seasons and for people like me, who can’t wait to get back out in the garden, starting seeds indoors [long before winter has ended] is a good option. However, some seeds do not transplant well and therefore, do no do well started indoors–at least not in the traditional manner.
The tubers [carrots, turnips, parsnips, beets, potatoes, radishes] should not be started indoors, when transplanting outdoors is the ultimate goal. The same is true of onions.
There are exceptions, however. I have begun some miniature carrots indoors in window boxes, where they will remain until harvested. If you have adequate indoor space and/or a heated greenhouse [where the tubers and bulbs an grow until harvest], these restrictions would not apply.