Basil is easy to grow from seed but is very sensitive to cold.
It is an annual, so cannot keep through Winter, but it is possible to sow successively to get crops anytime, providing right conditions can be replicated.
Rosemary is a perennial, but cropping a plant that has struggled to survive winter is maybe demanding too much, hence have a number of plants: some for cropping, and others for growing on.
Had more than a dozen successive sowings of Basil, but just did not get right conditions for them to thrive over the Winter this time round.
I'll be starting another batch in a heated propagator in next few days, but these are my usual 'grow over Summer', rather than Winter attempts!