Why sailcloth improved slowly in the age of sail

How much did age-of-sail navies try to improve sailcloth technology, and what limited them?

They improved weaving and manufacture as far as contemporary materials knowledge allowed, before steam machinery became the more important development path.

Age-of-sail navies improved sailcloth through changes to weaving, treatment, and manufacture. Progress was limited by the materials knowledge and production methods available. These were gradual developments rather than changes at the pace expected of modern materials science. The later shift of naval development toward engines and steam propulsion gave sailcloth a different place among naval priorities.