[Source:] Both of Chopin’s piano concerti have their merits, but
[1.] the Concerto in E minor is easier to take on:
[2.] ‘the F minor is more personal,
[3.] it is more difficult to understand the musical process; in terms of expression, this work is less brilliant.
The Concerto in E minor, obviously, is also
[2.] very personal,
but the [4.] objective brilliance of this work does help.’
I unfortunately don't understand Mr Ohlsson's explanation; the bolded words appear too broad and vague to me.