why does shaquille o'neal have a low per

Shaquille O'Neal had his lowest PER with a PER above 0 in a season in 2007-08, with a 17.1 rating.

Interpreted as:

Why does Shaquille O'Neal have a low per in a regular season?

	NAME	PER	SEASON	TM	GP	MPG	PPG	RPG	APG	SPG	BPG	FGM	FGA	FG%	3PA	3P%	FTM	FTA	FT%	TS%	OREB	DREB	TPG	MIN	PTS	REB	AST	STL	BLK	TOV	PF	+/-
1	Shaquille O'Neal S. O'Neal	17.1	2007-08	TOT	61	28.7	13.6	9.1	1.5	0.5	1.4	5.4	9.1	59.3	0.0		2.8	5.5	50.3	58.9	2.7	6.4	3.0	1,748	832	554	93	32	88	181	228	+5
2	Shaquille O'Neal S. O'Neal	17.4	2010-11	BOS	37	20.3	9.2	4.8	0.7	0.4	1.1	3.6	5.4	66.7	0.0		2.0	3.5	55.7	65.9	1.3	3.5	1.5	752	341	178	26	16	42	56	120	+193
3	Shaquille O'Neal S. O'Neal	17.9	2009-10	CLE	53	23.4	12.0	6.7	1.5	0.3	1.2	4.9	8.7	56.6	0.0	0.0	2.1	4.3	49.6	56.5	1.8	4.9	2.0	1,240	636	355	80	15	62	105	169	+93
4	Shaquille O'Neal S. O'Neal	21.7	2006-07	MIA	40	28.4	17.3	7.4	2.0	0.2	1.4	7.1	12.0	59.1	0.0		3.1	7.4	42.2	56.7	2.4	5.0	2.4	1,135	690	297	79	8	55	95	139	+40
5	Shaquille O'Neal S. O'Neal	22.3	2008-09	PHX	75	30.0	17.8	8.4	1.7	0.7	1.4	6.8	11.2	60.9	0.0	0.0	4.1	6.9	59.5	62.3	2.5	5.9	2.2	2,252	1,333	633	126	49	108	168	253	+140
6	Shaquille O'Neal S. O'Neal	22.9	1992-93	ORL	81	37.9	23.4	13.9	1.9	0.7	3.5	9.0	16.1	56.2	0.0	0.0	5.3	8.9	59.2	58.4	4.2	9.6	3.8	3,071	1,893	1,122	152	60	286	307	321
7	Shaquille O'Neal S. O'Neal	24.4	2005-06	MIA	59	30.6	20.0	9.2	1.9	0.4	1.8	8.1	13.6	60.0	0.0		3.7	8.0	46.9	58.6	2.9	6.3	2.8	1,806	1,181	541	113	23	104	168	230	+269
8	Shaquille O'Neal S. O'Neal	24.4	2003-04	LAL	67	36.8	21.5	11.5	2.9	0.5	2.5	8.3	14.1	58.4	0.0		4.9	10.1	49.0	57.8	3.7	7.8	2.9	2,464	1,439	769	196	34	166	195	225	+437
9	Shaquille O'Neal S. O'Neal	26.4	1995-96	ORL	54	36.0	26.6	11.0	2.9	0.6	2.1	11.0	19.1	57.3	0.0	50.0	4.6	9.5	48.7	57.0	3.4	7.7	2.9	1,946	1,434	596	155	34	115	155	193
10	Shaquille O'Neal S. O'Neal	27	2004-05	MIA	73	34.1	22.9	10.4	2.7	0.5	2.3	9.0	15.0	60.1	0.0		4.8	10.5	46.1	58.3	3.5	6.9	2.8	2,492	1,669	760	200	36	171	203	262	+470
11	Shaquille O'Neal S. O'Neal	27.1	1996-97	LAL	51	38.1	26.2	12.5	3.1	0.9	2.9	10.8	19.4	55.7	0.1	0.0	4.5	9.4	48.4	55.6	3.8	8.7	2.9	1,941	1,336	640	159	46	147	146	180	+268
12	Shaquille O'Neal S. O'Neal	28.5	1993-94	ORL	81	39.8	29.3	13.2	2.4	0.9	2.9	11.8	19.6	59.9	0.0	0.0	5.8	10.5	55.4	60.5	4.7	8.5	2.7	3,224	2,377	1,072	195	76	231	222	281
13	Shaquille O'Neal S. O'Neal	28.6	1994-95	ORL	79	37.0	29.3	11.4	2.7	0.9	2.4	11.8	20.2	58.3	0.1	0.0	5.8	10.8	53.3	58.8	4.2	7.3	2.6	2,923	2,315	901	214	73	192	204	258
14	Shaquille O'Neal S. O'Neal	28.8	1997-98	LAL	60	36.3	28.3	11.4	2.4	0.7	2.4	11.2	19.1	58.4	0.0		6.0	11.4	52.7	58.7	3.5	7.9	2.9	2,175	1,699	681	142	39	144	175	193	+649
15	Shaquille O'Neal S. O'Neal	29.5	2002-03	LAL	67	37.8	27.5	11.1	3.1	0.6	2.4	10.4	18.1	57.4	0.0		6.7	10.8	62.2	60.2	3.9	7.2	2.9	2,535	1,841	742	206	38	159	196	229	+363
16	Shaquille O'Neal S. O'Neal	29.7	2001-02	LAL	67	36.1	27.2	10.7	3.0	0.6	2.0	10.6	18.3	57.9	0.0	0.0	5.9	10.7	55.5	59.0	3.5	7.2	2.6	2,422	1,822	715	200	41	137	171	199	+566
17	Shaquille O'Neal S. O'Neal	30.2	2000-01	LAL	74	39.5	28.7	12.7	3.7	0.6	2.8	11.0	19.2	57.2	0.0	0.0	6.7	13.1	51.3	57.4	3.9	8.8	2.9	2,924	2,125	940	277	47	204	218	256	+463
18	Shaquille O'Neal S. O'Neal	30.6	1998-99	LAL	49	34.8	26.3	10.7	2.3	0.7	1.7	10.4	18.1	57.6	0.0	0.0	5.5	10.2	54.0	58.4	3.8	6.9	2.5	1,705	1,289	525	114	36	82	122	155	+225
19	Shaquille O'Neal S. O'Neal	30.6	1999-00	LAL	79	40.0	29.7	13.6	3.8	0.5	3.0	12.1	21.1	57.4	0.0	0.0	5.5	10.4	52.4	57.8	4.3	9.4	2.8	3,163	2,344	1,078	299	36	239	223	255	+706