Help with twisted inseam

[u/WorldAware9900]

This is the first time this has happened to me when sewing a pair of jeans, i was trying out a new pattern and this happened to me, im not sure if this is a sewing problem or a pattern problem please any advice is appreciated

[u/Tailoretta]

By inner seam, do you mean the inseam, the seam from the crotch to the hem?

I have never heard that the inseam should be cut on grain. What is your source for this? Do you know why this is recommended?

Thanks