Why do people say the PS2 started out slow?

[redspear]

whatever said:

10/2000	PS2	453,500	453,500	11/2006	PS3	220,500	220,500
11/2000	PS2	214,000	667,500	12/2006	PS3	533,250	753.750
12/2000	PS2	642,250	1,309,750	01/2007	PS3	273,000	1,026,750
01/2001	PS2	274,250	1,584,000	02/2007	PS3	133,750	1,160,500
02/2001	PS2	262,000	1,846,000	03/2007	PS3
03/2001	PS2	604,500	2,450,500	04/2007	PS3

 Just to put this out, here are the NA numbers for PS2 and PS3.  Note that from 03/2001 forward, the PS2 was the number 1 console, something the PS3 won't be anything soon. 

 I just don't see a 604,500 unit march or april for the PS3

It is scarily similiar to the GC in Japan. It is outselling on a weekly basis but only by a few hundred for the same time period but it has a lower overall total.