import pandas as pd
import dask.dataframe as dd

frames1 = [dd.from_pandas(pd.DataFrame(index=[1, 2, 3], data=dict(a=[1, 2, 3]))) for i
           in
           range(3)]
dd.concat(frames1).compute()  # works
frames1[0].join(frames1[1]).compute()  # works

frames2 = [dd.from_pandas(pd.DataFrame(index=[1, 2, 3])) for i in
           range(3)]
frames2[0].join(frames2[1]).compute()  # works
dd.concat(frames2).compute()  # fails