Prepend words to dict. Why so many time?

[hvprvtr]

Hello. I try to bruteforce hashes by dict, but with prepended word abc.
Dict without this word (-a0) processed for 2 mins.
But if i run next modes, time rise to 7 days. Why so long?

(abc.txt contains word "abc" only)

Code:

hashcat.exe -a7 -m22000 lists\wifi.hc22000 abc dict.txt
hashcat.exe -a1 -m22000 lists\wifi.hc22000 abc.txt dict.txt